4th Edoardo Amaldi Conference on Gravitational Waves
ABSTRACTS
RESONANT MASS DETECTORS - Friday
AGUIAR
O. D. Aguiar , L. A. Andrade , C. A. Costa , J. C. N. de Ara˙jo , E. C. del Rey Neto, C. Frajuca, G. Frossati,
S. R. Furtado, V. S. Furtado, N. S. Magalhaes , R. M. Marinho Jr., E. S. Matos, J. L. Melo, O. D. Miranda,
N. F. Oliveira Jr., K. L. Ribeiro, K. B. M. Salles , W. F. Velloso Jr.
Instituto Nacional de Pesquisas Espaciais, Jose dos Campos, Sao Paulo, Brazil
The Status of the Brazilian Spherical Detector
The first phase of the Brazilian Graviton Project is the construction and operation of the gravitational wave
detector Mario Schenberg at the Physics Institute of the University of Sao Paulo.
This gravitational wave spherical antenna is planned to feature a sensitivity better than h = 10 -21 Hz-1/2 at the
(3.0 ± 0.2) kHz bandwidth, and to work not only as a detector, but also as a testbed for the development of
new technologies. Here we present the status of this detector.
POSTER
AGUIAR
S. R. Furtado, O. D. Aguiar
Instituto Nacional de Pesquisas Espaciais ñ INPE
N. F. Oliveira Jr.
University of Sao Paulo
Fast Cooling Techniques For Gravitational Waves Antennas
The resonant-mass technique for the detection of Gravitational Waves may involve in a near future the
cooling of very great masses (about 100 tons) from room temperature (300K) to extreme cryogenic
temperatures (20mK). To cool these detectors down to cryogenic temperatures an exchange gas (helium) is
used and the heat is removed from the antenna to the cold reservoir by thermal conduction and natural
convection. With the current technique, cooling times of about one month can be obtained for cylindrical
bar antennas of 2.5 tons. In the case this same technique were used to cool a 100-ton spherical antenna, the
cooling time would be about 10 months, making the operation of these antennas impracticable. In this work
we study the cooling technique mentioned above and others, such as thermal switching and forced
convection, from room temperature down to liquid nitrogen temperature (77K), using an aluminum 19kg25cm-diameter truncated icosahedron.
POSTER
AGUIAR
K. L. Ribeiro (1), E. Ivanov (2), D. G. Blair (2), M. Tobar (2), O. D. Aguiar (1), C. Frajuca (3)
(1) Instituto Nacional de Pesquisas Espaciais, S„o JosÈ dos Campos, SP, Brazil
(2) University of Western Australia, Perth, Australia
(3) Centro Federal de Ensino TecnolÛgico de S„o Paulo, S„o Paulo, SP, Brazil
Improvements In The Noise Floor Of The Gravitational Wave Antenna Niobe
The gravity wave detector at the University of Western Australia (UWA) is based on a bending flap of 0.43
kg tuned near the fundamental resonant frequency of a 1.5-ton resonant-bar of 710 Hz. The displacement of
the bending flap is monitored with a 9.5 GHz superconducting re-entrant cavity transducer. The
performance of transducer is related with the development of a low noise microwave pump oscillator to
Amaldi 4
Abstracts
Page 1
drive the transducer. In this work we describe how we improve the quality of the existing microwave pump
oscillator using a second servo frequency control system and how this improvement can increase the
sensitivity of the detector.
POSTER
AHMEDJONOV
A.R. Ahmedjonov, R. Kalonov and K. Khasanov
Samarkand State University
About Phenomenon Of Electromagnetic Field Influence On Gravitational Mass
The experience were carried out with samples: magnetite Fe2+ Fe3+ O4+, iron hydroxide, gold and quartz
powder-like formed with the sizes of particles from 0.001 mm up to 1 mm. The influence on magnetite was
carried out with the help of a constant magnet with value of field strength density about 1000 ersted/cm2.
The sample was located in a porcelain cup, the constant magnet was brought which was included on time
15-30 seconds. After switching-off of a magnet the powder was located in desiccator on time 5-10 minutes,
then was weighed on scale of the mark Sartorius-2045, max. 30 gr, accuracy d=0,001mgr. The interaction
of a magnetic field with magnetite, weighing repeatedly recurred. The samples of powders iron hydroxide,
gold and quartz were weighed by a way of shooting from a porcelain cup of electronic scale, during which
the friction of particles among themselves and them electrization was carried out. In the performed
experiences the reduction of gravitational mass caused by influence of external fields in time and space has
been observed.
POSTER
ALUIGI
P. Galletti, A. Aluigi
A Detector For Gravitational Waves
The paper consists of two parts. The first part describes an electrical detector that was conceived and built
in the 1994. The instrument is very simple and consists of Wheatstone bridge in one of the two arms is
located a cadminum sulfide photoresistor and illuminated with a constant source of light emitted by a
vacuum diode. It is a powerful instrument capable to detect most highly energetic phenomena occurring in
the Visible Universe. The instrument in operating continuously since 26 April 1994 and graphs produced
with the data recordered until today will be also presented. In the second part of paper a series of magnetic
sensors which are capable to intercept Gravitational Waves are described. The first one of those sensors
was built in 1970 but, at that time, its operating was not well understood. In the 1994, after the
photoresistor detector was operating, a second sensor was built and whose behavior is in accordance with
the signal coming from the electrical detector. A design of a new sensor which uses superconducting
magnets and capable to generate high forces will be also presented in the paper.
This report describes a detector one of us (P. Galletti) conceived and built in 1994. The instrument is
operating continuously since 26 April 1994 and graphs produced with the data recorded until 30 June 2000
are, here, presented. The behaviour of this simple instrument, which consists of Wheatstone bridge in one
of the two arms is located a cadmium sulphide photoresistor and illuminated with a constant source of light
emitted by a vacuum diode, was considered, since the beginning, "anomalous". After more than six year
experiments and observations on its operating, we have decided to make these results known. Perhaps, it
is superfluous to remark that the instrument was built with other aims and the discovery of its anomalous
behavior is the result of a combination of fortuitous circumstances happened in the beginning of 1994.
Amaldi 4
Abstracts
Page 2
OPERATING DETECTORS - Tuesday
ANDO
M. Ando and the TAMA collaboration
University of Tokyo
Current Status of TAMA
TAMA is a Japanese project to construct and operate an interferometric GW detector with a 300-m baseline
length at the Mitaka campus of the National Astronomical Observatory in Tokyo. The TAMA detector,
TAMA300, has been improved dramatically since the last Amaldi conference (California, 1999), when we
showed the first sensitivity curve with the final interferometer configuration except power recycling. So far
the detector has been operated with sufficient sensitivity and stability to observe GW events at the center of
our galaxy. It was operated stably and continuously over several hours in typical cases, and over 24 hours
in the best case. The noise-equivalent sensitivity is 5x10-21 1/Hz at the floor level. With this sensitivity, a
signal-to-noise ratio (SNR) of 30 is expected for gravitational waves generated by a coalescence of
1.4Msoler-1.4Msoler binary neutron stars at 10kpc distance. In the conference, we will show the current
status of the TAMA300 interferometer, and results from observation runs.
OPTICAL SUBSYSTEMS - Thursday
ARAI
K. Arai and the TAMA300 project
National Astronomical Observatory
Sensing and controls for power-recycling of TAMA300
The application of power-recycling to a Fabry-Perot-Michelson interferometer TAMA300 is planned. I
discuss sensing and control scheme of power-recycling for TAMA300. Particularly application of a length
sensing scheme using demodulation with local oscillators at third harmonic frequency of phase modulation
is described.
OVERVIEWS - Monday
ASTONE
P. Astone
INFN Frascati Rome
Resonant Mass Detectors
I will review the main features of the resonant mass g.w. detectors. After a brief survey of the main
characteristics of the presently operating antennas (with a particular attention to the news regarding each
one of them), I will present some recent experimental results.
DATA ANALYSIS - Tuesday
ASTONE
P. Astone
INFN Frascati Rome
Coincidence Analysis In Gravitational Wave Experiments
The search for short events with g.w. detectors is a very important task. The nature of the noise and of the
signals is such that coincidence analyses using two or more detectors are necessary. The present operating
resonant bar detectors are in continuous operation since many years (with interruptions due to maintenance
and/or upgrading of the apparatuses) and various coincidence analyses have been performed. The recent
analysis, within IGEC (International Gravitational Event Collaboration), has lead to a new upper limit for
galactic events. Since the very beginning of the continuous operation (in 1991) and until the most recent
IGEC data exchange, we have studied various problems and we have learned about this kind of analyses.
We will point out some of the most critical problems and we will describe algorithms aimed at solving
them.
Amaldi 4
Abstracts
Page 3
POSTER
BAGGIO
L. Baggio, E. Rocco, G.A. Prodi, S. Vitale - Univ. of Trento and INFN
M. Cerdonio - Univ. of Padova and INFN
A. Ortolan, G. Vedovato - INFN LNL
I.S. Heng - LSU
IGEC Toolbox For Coincidence Search
The standard IGEC approach to detection of gw with many detectors is simple time coincidence search. We
issue the problems of false alarm and false dismissal assessment, particularly in the case of non-stationary
(and possibly correlated) background noise. The observative results are based on maximum likelihood
methods.
POSTER
BALAKIN
A.B.Balakin, R.A.Daishev, Z.G.Murzhakhanov, A.F.Skochilov
Kazan State University, Kazan, Russia
Gravitational Wave Project Dulkyn: Concept, Status And Perspectives
Developing the idea of M.Scully concerning the compact active laser interferometric gravity detector, we
have elaborated and constructed the active two-contours pentagonal interferometer with running waves and
the trigonal interferometer with standing waves for the detection of infra-low-frequency variations of the
gravity field.
The talk is planned to include the following items:
- concept of detection of the periodic infra-low-frequency gravitational radiation from relativistic binaries;
- structure and technical parameters of the pentagonal laser interferometer;
- theory of response of the compact non-resonant active electro- elasto-dynamical system on the action of
periodic gravitational radiation;
- description of the so-called Lunar test, destined for the detection of 12-hours tidal variations of the
geophysical potential;
- description of the system of stabilization of the phase difference of the optical flows in reference and
signal resonators;
- discussion of the signal processing models;
- project of the measurements of the Earth rotation irregularities.
POSTER
BARBER
T. Barber, J. Winterflood, L. Ju, D.G. Blair
Department of Physics, University of Western Australia
Geometric Anti-Spring Euler Isolators
Euler springs which give near ideal vibration isolation (See High Performance vibration isolation using
springs in Euler column buckling mode, J. Winterflood D.G. Blair, this conference) can be tuned to low
frequencies through a geometric anti-spring effect. By controlling the springs boundary conditions vertical
mode frequencies significantly below 1 Hz can be achieved. We will present a description of the
mechanisms of the geometric anti-spring and the latest experimental measurements.
Amaldi 4
Abstracts
Page 4
POSTER
BARONE
F.Barone1,E.Calloni2, R.De Rosa2, L.Di Fiore3, A.Eleuteri2, L.Milano2, K.Qipiani3
1
Universita' di Salerno and INFN sez.Napoli
Universita' di Napoli Federico II and INFN sez.Napoli
3
INFN sez.Napoli
2
An Adaptive Optics Approach To The Reduction Of Misalignments And Beam Jitters In Gravitational Wave
Interferometers
Effects of misalignments and beam jitters in long baseline interferometric gravitational wave detectors are
briefly resumed, with particular attention to the beam fluctuations in tilts and waist diameter and position
and the resulting constrains on interferometric asymmetries. An adaptive optics approach for correction of
beam fluctuations is discussed. As a preliminary step, a facility in Napoli Virgo Lab has been set up. This
facility consists in an Adaptive Optics Device, based on commercial micro-machined Deformable Mirrors,
produced by Flexible Technologies, a Shack-Hartmann detection scheme and a PC for digital acquisition
and control. Preliminary results are shown and compared with the requested sensitivity of gravitational
interferometers. Being the band-pass of the overall system too low, improvements on electronic acquisition
and filtering are discussed, with particular attention to the use of fast real-time digital control systems.
Finally alternative phase-front detection techniques and suitable feed-back improvements are evaluated and
discussed.
SOURCES - Monday
BENACQUISTA
M. Benacquista
Montana State University-Billings
Black Hole Binaries in Globular Clusters as LISA Sources
Globular clusters have been proposed as nurseries for black hole binaries. The majority of these binaries
will be ejected from their host globular cluster early in the history of the cluster and will merge within a
Hubble time. The scenario which produces these binaries also allows for a remnant population of binaries
which will remain in the host cluster. The large eccentricities of these binaries will allow for their detection
with LISA even though their fundamental gravitational wave frequency is well below LISA's sensitivity
band.
CONFIGURATIONS - Wednesday
BEYERSDORF
P. Beyersdorf
National Astronomical Observatory of Japan
Results from the Stanford 10m Sagnac Interferometer
Future advanced interferometric gravitational wave detectors will be limited by thermal distortions
induced by high circulating power. The all-reflective configuration based on the Sagnac interferometer
presented here is well suited to operation with high circulating power. A polarization scheme is presented
that allows the interferometer to be used in a reciprocal configuration, so that static imperfections and
thermally induced distortions of the beamsplitter and optics have a minimal effect on the interference
contrast. The necessary low-frequency response of the interferometer requires delay-lines in the arms. To
deal with the noise introduced by scattered light in the delay lines, a laser frequency sweep frequency
shifts the scattered light so that it does not produce noise in the measurement band. Results from the
10m all-reflective prototype interferometer with suspended optics are presented. The prototype
incorporates the laser frequency sweep to provide a shot-noise-limited phase sensitivity of
=10-9 rad Hz-1/2 at frequencies as low as 200 Hz. Scaling this prototype to several kilometers with
kilowatts of circulating power requires several technical improvements in high-power solid-state lasers,
Amaldi 4
Abstracts
Page 5
second harmonic generation, and the fabrication of large mirrors, which are likely to be made in the next
10 years.
BIGNOTO
M. Bignoto, M. Bonaldi, M. Cerdonion, L. Conti, A Heidmann, J.A. Lobo, A. Ortolan, M. Pinard, G.A.
Podi, L. Taffarello, S. Vitale, J-P Zendri
INFN – LNL
A Wideband And Sensitive Gw Detector For Khz Frequencies: The Dual Sphere
We discuss the new concept of a sensitive and wideband detector, consisting of a solid sphere nested inside
a hollow one: the dual sphere. The advantage is that it would be thus possible to keep both the omnidirectionality and high sensitivity of the spherical geometry without giving up the wide band. In the few
kHz range the dual sphere would be complementary to ‘advanced’ interferometers. We also discuss the
main technological and scientific challenges that the construction of such a system poses with particular
regard to material choice, fabrication, cooling, suspension and readout.
FUTURE DETECTORS - Friday
BILENKO
I.A. Bilenko, V.B. Braginsky N.Markova Yu.
Moscow State university
Thermal and Excess Noise in Suspension Fibers
The spectral density of the equilibrium noise can be reduced by increasing the quality factor for all modes
of mechanical vibrations in test mass suspension system. At the same time, the existence of an extra
(excess) noise of the nonthermal origin is possible. Their source can be the development of microcraks,
migrations of dislocations and other defects in the suspension. The experiments carried out already have
shown the presence of such a noise in metal wires under high tension. Application of new measurement
technique allows us to improve the sensitivity of the measurement and test the fused silica suspension
prototype. The results and discussions will be presented.
DATA ANALYSIS - Tuesday
BLACKBURN
J. K. Blackburn
California Institute of Technology
LDAS/LSC Mock Data Challenges
The LIGO Science Collaboration in conjuction with the LIGO Laboratory is performing a series of
software and data analysis tests of the LIGO Data Analysis System (LDAS) and the LIGO Algorithm
Library (LAL). Several of these tests, known as Mock-Data-Challenges (MDC) have been successfully
completed. They have verified the ability of LDAS to gather data stored by the LIGO Data Aquisition
System (DAQS), pre-condition this data and then hand off the data to the parallel data analysis search
engines running in the LIGO Beowulf clusters. Results from these searches are then parsed and stored in
the LIGO database. The details of these test challenges and are described and current results presented.
RESONANT MASS DETECTORS - Friday
BLAIR
D. Blair1, R. Burman1, R. Clay2, D. Coward1, E. Ivanov1, G. Mazzitelli3, F. van Kann1, E.Winterflood1
1
University of Western Australia, 2University of Adelaide, 3INFN Frascati
Improved Sensitivity of Niobe in 2001 and Search for Anomalous Cosmic Ray Events
Niobé has been upgraded with improved vibration isolation, a low noise microwave amplifier with noise
temperature just 10 times the quantum limit and improved cryopumps. It was brought into operation in Feb
2001. Cryogenic heat leaks have been halved reducing the liquid helium consumption to about 12 litres per
Amaldi 4
Abstracts
Page 6
day. The non-contacting superconducting cavity transducer readout is pumped by a composite microwave
source based on a 77K sapphire oscillator and a low noise frequency synthesiser. This non-ideal
configuration means that the broadband noise floor is limited by pump oscillator noise, and is about 20dB
improved compared with previous operation. To date data has been acquired using dual lock-in amplifier
demodulation at the normal mode frequencies of 695Hz and 713Hz, sampled at 10Hz. At 1 sec integration
time using a non-optimised zop filter the noise temperature is below 1mK, corresponding to a strain
sensitivity for millisecond bursts of 4-5 x 10-19. Niobé's Adelaide University cosmic ray shower array has
been operated in coincidence with Niobé to search for anomalous excitations of the type observed with
Nautilus. Latest results will be presented.
POSTER
BOLDT
E. Boldt, A. Levinson, M. Loewenstein
NASA's Goddard Space Flight Center
Black-Hole Galactic Nuclei: A High Energy Perspective
The highest energy cosmic rays observed must come from sources within 100 Mpc. The number of
elliptical galaxies harboring a core MDO (Massive Dark Object) within this present-epoch volume is now
known to be remarkably large. These MDOs are the quasar remnant black holes ('dead quasars') expected
in the present epoch. Guided by the membrane paradigm, as applied to accreting spun-up black holes, we
here consider them as potential generators of ultra-relativistic cosmic ray particles. These quasar remnants
would yield gamma-ray emission of TeV curvature radiation characteristic of such compact dynamos.
Coupled with high resolution spectral/spatial studies of AGN X-ray emission from close to its black-hole
event horizon, observations of TeV curvature radiation from MDOs hold the promise of distinguishing the
geometry underlying these two kinds of black-hole based galactic nuclei, thereby providing information
necessary for interpreting associated occurrences exhibiting gravitational radiation.
OPTICAL SUBSYSTEMS - Thursday
BONDU
F. Bondu
CNRS - ILGA Observatoire de la Cote d'Azur
The Virgo Injection System : Laser, Long Mode-cleaner, Alignment and Locking Sequence
Abstract not available.
DATA ANALYSIS - Tuesday
BOSE
S. Bose
Albert Einstein Institute
Network Gravitational-Wave Analysis: Searching For Binary Inspiral Signals
Coherent and coincident strategies for analysing data from multiple terrestrial interferometers, with
arbitrary orientations and locations, to search for 2PN binary-inspiral waveforms will be presented. A
``robust'' multi-detector statistic for searches in non-Gaussian detector noise will be discussed. The number
of filters required for and computational costs associated with these different search strategies will be
compared.
Amaldi 4
Abstracts
Page 7
ISOLATION and SUSPENSION - Wednesday
BRACCINI
S. Braccini
Istituto Nazionale di Fisica Nucleare
The VIRGO Suspensions
The VIRGO suspensions have been designed to isolate each optical component of the interferometric
detector from seismic noise starting from about 4 Hz. All the seven suspensions of the VIRGO central
interferometer are presently in operation, while the assembly of the last two ones, for the terminal mirrors,
is in progress. The design of the system and its performances are described in this talk.
SOURCES - Monday
BRUEGMANN
B. Bruegmann
Max-Planck-Institut fuer Gravitationsphysik
Making Waves With Black Holes
Numerical relativity is closing in on a long standing goal, the simulation of the plunge that marks the end of
the inspiral of two orbiting black holes. In this talk I will discuss recent progress in numerical relativity
related to black hole excision, new lapse and shift conditions, and an interface between full non-linear and
perturbative evolutions. The new developments presented here make it possible for the first time to start
with a particular initial data set and to compute a complete waveform for the plunge, merger, and ringdown of two black holes.
SPACECRAFT METHODS - Wednesday
BUCHMAN
S. Buchman
Stanford University
LISA Technology Demonstration Mission
Abstract not available.
SOURCES - Monday
BUONANNO
A. Buonanno
California Institute of Technology
Gravitational Waves From Inspiraling Binary Black Holes
Binary black holes are among the most promising sources for earth-based gravitational-wave
interferometers. We summarize the analytic state-of-the-art techniques developed during the last years to
better describe the late dynamical evolution of binary black holes, discussing their performances and
limitations. These approaches could provide templates for gravitational waves emitted throughout the
adiabatic inspiraling phase up to the plunge for binary black holes of comparable masses.
Amaldi 4
Abstracts
Page 8
CONFIGURATIONS - Wednesday
BUONANNO
A. Buonanno and Y. Chen
California Institute of Technology
Signal-Recycled Laser-Interferometer Gravitational-Wave Detectors As Optical Springs: Beating The
Standard Quantum Limit
It has long been thought that the sensitivity of laser-interferometer gravitational-wave detectors is limited
by the free-mass standard quantum limit, unless radical redesigns of the interferometers or modifications
of their input/output optics are introduced. Using a quantum mechanical approach, we show that in a
gravitational-wave interferometer composed of arm cavities and a signal recycling cavity, e.g., the LIGOII configuration, (i) quantum shot noise and quantum radiation-pressure-fluctuation noise are dynamically
correlated, (ii) the radiation pressure force acting on the mirrors not only disturbs the motion of the free
masses randomly, but also and more fundamentally, makes them respond to forces as though they were
connected to a spring with a specific rigidity. This oscillatory response gives rise to a much richer
dynamics than previously known, which enhances the possibilities for reshaping the noise curves and, if
thermal noise can also be pushed low enough, will enable to beat the standard quantum limit.
POSTER
BURSTON
R. Burston and A. Lun
Monash University
Abstract not available.
LASERS and OPTICS - Thursday
BYER
R. Byer
Stanford University
Progress in Edge-Pumped Slab Lasers
Abstract not available.
ISOLATION and SUSPENSION - Wednesday
CAGNOLI
G. Cagnoli
IGR, Glasgow
Silica Research in Glasgow
The Glasgow group is involved in the construction of the GEO600 interferometer as well as in R&D actvity
on technology for advanced gravitational wave detectors. GEO600 will be the first GW detector using
quasi-monolithic silica suspensions in order to decrease thermal noise significantly with respect to steel
wire suspensions. Results concerning GEO600 suspension mounting and performance will be shown. Silica
is also a very promising material for advanced detectors. R&D activity has been carried out to understand
better how thermal noise in the suspensions and in the test masses affects the detector sensitivity, and
results will be presented.
Amaldi 4
Abstracts
Page 9
POSTER
CEAPA
A.C.V. Ceapa
DistrigazSud Bucharest
On The Subquantum Origin Of The Gravitational Waves: Consequences
The classical principle of the physical determination of equations is validated in Einstein’s relativity theory
by his tacitly ignored 1905 operational derivation of Lorentz transformation. Therefore, the relativistic
quantum mechanics built on Einstein’s energy-momentum relationship can provide further physical
information. Consider in this aim the spinorial transcription of the Dirac equation, viz.
ih[+(.)-o] = -moc, ih[-(.)-o] = -moc, (1) as it was firstly deduced by der Waerden from the
operatorial relativistic energy-momentum relationship [E/c-(.p)][E/c+(.p)]=mo2c2, (2) where h is the
reduced Planck constant, (/x,/y,/z), o=/(ct), ,  are two-component spinors, (x,y,z) are the
Pauli 2x2 matrices, and E, p, mo are, respectively, the energy, linear momentum and rest mass of a free
particle. A comparison of Eqs. (1) with the equation iho1=(E/c)1+(K/c)2, describing a weak coupling
in the quantum mechanics, shows that K=moc2 and suggests that a leakage of components between two
physical entities which, associated to (.p) in (2), should spin in opposite directions. With ci, Si=(h/2)i
(i are Dirac 4x4 matrices, Latin indices run from 1 to 3) defining, respectively, the velocity operator and
spin operator, the relationship =-(i/2)(x) and the commutation relations [ci,i] = 0, it is suggested that
c are peripheral velocities of those spinning physical entities. This semi-classical model of Dirac particle
is supported [1] by the splitting of the Dirac spinors in the eigenbasis of the velocity operator corresponding
to +c and -c, as well as in components of opposite helicities and, finally, by a derivation of the maximal
acceleration aM = 2moc3/h as a quantum quantity from the classical acceleration a=c 2/r with r==C/2, where
C is the reduced Compton wavelength. The rigorous quantum mechanical derivation of the frequency
operator ‘i = P+ iP+ +P-iP-, where P=[1sign(E)]/2 project onto positive and negative energy states,
and i are components of the quantity =-2c5p/h appearing in the Dirac hamiltonian, confirms the semiclassical model, associating the frequencies  = 2moc2/h to the two systems of subquantum particles
spinning tangently, in opposite directions. within a Dirac particle. The dependence of the weak
gravitational wave potentials also on the time rate of change of mass suggests that, by altering the coupling
of the systems existing in a Dirac particle, such waves, carrying subquantum energy, can be physically
generated. The strength of the subquantum gravitational waves depends exclusively on our techniques.
POSTER
CHARLTON
P. R. Charlton, S. B. Anderson, J. K. Blackburn, J. Edlund, F. A. Jenet, A. Lazzarini,
T. A. Prince, L. Wen
California Institute of Technology
Detection Of Gravitational Waves From Inspiralling Compact Binaries Using A Fast Chirp Transform
The Fast Chirp Transform (FCT) of provides a powerful formalism for the detection of signals with
variable frequency, in much the same way that the Fourier transform provides a formalism for the detection
of constant frequency signals. The FCT algorithm has significant applications in the detection of
gravitational waves, particularly the gravitational wave signal produced by an inspiralling compact binary.
We report on progress towards a parallelised search code to identify inspiral events in interferometer data
and estimate the mass parameters.
POSTER
CHECHIN
T.B.Omarov, I.V. Strokova and L.M. Chechin
Astrophysical Instutute NAS Kazakhstan
Gravitational Radiation Of Nonlinear Cosmic String
We present the power of gravitational energy radiation of cosmic string that performes nonlinear
oscillations.
Amaldi 4
Abstracts
Page 10
POSTER
CHENG
Y. Cheng, J. Winterflood, Z. Zhou, L. Ju, D. Blair
The University of Western Australia
Tilt Sensor And Servo Control System
When very low frequency vibration isolators are used in gravitational wave detection, there is an intrinsic
coupling between tilt noise and translation. Thus to achieve high performance vibration isolation, it is
important that tilt motion be suppressed. A novel system has been developed to measure small seismic tilts
by using a walk-off sensor. A servo control system using piezoelectric actuators can effectively suppress
tilt noise. It has been used to investigate the tilt amplitude of seismic land wave, hence allowing a direct
determination of the seismic wave velocity. Latest results will be presented.
FUTURE DETECTORS - Friday
CONTI
M. Bignotto, M. Bonaldi, M. Cerdonio, L. Conti, W. Duffy Jr., A. Heidmann, J.A. Lobo, A. Ortolan, M.
Pinard, G.A. Prodi, L. Taffarelo, S. Vitale, J.P. Zendri
A Wideband and Sensitive GW Detector for kHz Frequencies: The Dual Sphere
We discuss the new concept of a sensitive and wideband detector, consisting of a solid sphere nested inside
a hollow one: the dual sphere. The advantage is that it would be thus possible to keep both the omnidiectionality and high sensitivity of the spherical geometry without giving up the wideband. In the few
kHz range the dual sphere would be complementary to ‘advanced’ interferometers. We also discuss the
main technological and scientific challenges that the construction of such a system poses with particular
regard to material choice, fabrication, cooling, suspension and readout.
SOURCES - Monday
CORNISH
N. Cornish
Montana State University
Measuring The Cosmic Gravitational Wave Background
The gravitational wave sky, like the microwave sky, is expected to consist of isolated bright sources
superimposed on a diffuse gravitational wave background. The background radiation has two components:
a confusion limited background from unresolved astrophysical sources; and a cosmological component
formed during the birth of the universe. A great deal could be learned by measuring this Cosmic
Gravitational-wave Background (CGB), but detecting the CGB presents a significant technological
challenge. The signal strength is expected to be extremely weak, and there will be competition from
unresolved astrophysical foregrounds such as white dwarf binaries. I will discuss strategies for measuring
and mapping the gravitational wave background with LISA and LISA follow-on missions.
SOURCES - Monday
COWARD
D. M. Coward, R. R. Burman and D. G. Blair
The University of Western Australia
Simulating A Stochastic Background Of Gravitational Waves From Neutron Star Formation At
Cosmological Distances
We develop a temporal simulation of the potentially detectable gravitational wave background from
neutron star formation at cosmological distances. By using a recent model for the evolving star formation
rate, we investigate the statistical distribution of gravitational wave amplitudes due to supernovae that
result in neutron star formation in the Einstein-de Sitter cosmology. We find that the gravitational wave
amplitude distribution in our frame is highly skewed with skewness related to the distribution of sources,
Amaldi 4
Abstracts
Page 11
and that the potentially detectable gravitational wave strain is dominated by sources at a redshift of 2-3.
Time traces of the simulation, using selected waveforms, are presented graphically and are also made
available as web-based audio files. The method developed can readily be extended to different
cosmologies, as well as to incorporate other waveforms and source types.
POSTER
COWARD
D Coward, R Burman, S Woodings and D Blair
The University of Western Australia
Cosmology and the Supernova Count Rate
The rate of supernovae occurring throughout the Universe, as potentially observed on Earth, is dependent
on several factors, which we highlight in this poster. Cosmological effects become significant for sources
at redshifts beyond about 0.5. We use three currently popular cosmologies, the critical density Einstein-de
Sitter model, an open model and a "flat-lambda" model. Observations using the Hubble Space Telescope
and ground-based telescopes reveal that the rate of star formation was greater at earlier epochs. Because of
the short lifetimes of the progenitor stars, the rate of core-collapse supernovae closely tracks the star
formation rate. The supernova event rate equation depends on cosmology and the evolving star formation
rate. The supernova event rate equation depends on cosmology and the evolving star formation rate.
OPERATING DETECTORS - Tuesday
CRUISE
R. Ingley & A. M. Cruise
University of Birmingham
Control System, Data Reduction And Noise In The Birmingham Prototype 221mhz Gravity Wave Detector
The sensitivity of the laboratory prototype 221MHz gravity wave detector is currently of the order 1013
/Hz, while a sensitivity of 10^(-17) to 10^(-30)/rtHz would be more appropriate for making astronomical
observations. Sources of thermal and environmental noise limiting the sensitivity are identified and
compared with the parameters needed to produce an improved sensitivity. Details of the control system,
data acquisition and data reduction routines will be presented together with early operational data.
POSTER
D’ANTONIO
S. D'Antonio
Frascati National Laboratory INFN
On-Line Data Filters For Gravitational Wave Detectors
One of the problems encountered with the gravitational wave detectors when searching for small signals
embedded into noise is due to the fact that the noise cannot be easily modeled since it has often a non
stationary nature. For the search of delta-like g.w. signals we have implemented three matched filters
operating on-line, which optimize the signal-to-noise ratio according to the noise characteristics. The three
filters, each one with its own noise spectrum differing one spectrum from each other for the different set of
employed data, operate simultaneously. Then the filter output is chosen which experimentally gives the
best signal-to-noise ratio.
Amaldi 4
Abstracts
Page 12
OVERVIEWS - Monday
DANZMANN
K. Danzmann
Uiversity of Hannover and Max-Planck-Institut fuer Gravitationsphysik
Space Interferometers
LISA is a collaborative ESA/NASA space mission for the detection of low-frequency gravitational waves.
It is currently foreseen to be launched in August of 2011 with a technology demonstration precursor
mission in August 2006.
POSTER
DE ARAUJO
J.C. de Araujo, O.D. Miranda and O.D. Aguiar
Instituto Nacional de Pesquisas Espaciais
Background of gravitational waves from population III black
We study the generation of a stochastic background of gravitational waves (GWs) produced from a
population of core-collapse supernovae, which form black holes in scenarios of structure formation. We
obtain, for example, that the formation of a population (III) of black holes, in an open CDM scenario with
M = 0.25 (matter density parameter), could generate a stochastic background of GWs with amplitudes h BG
 (2-8) x 10-25 and corresponding closure density of GW  (1-2) x 10-9, at the frequency band obs  20-100
Hz (assuming an efficiency of generation of GWs  ~ 7 x 10-4. It will be possible to detect this isotropic
background of GWs, in the future, by correlating signals of a pair of advanced LIGO observatories (LIGO
III) at a signal-to-noise ratio (SNR) of  6. Once such a background is detected it will be possible to impose
constraints on the epoch when the formation of the first stars occurred.
RESONANT MASS DETECTORS - Friday
DE ROSA
M. De Rosa, F. Marin, L. Conti, M. Cerdonio, L.Taffarello, J-P Zendri, G.A. Prodi
Istituto Nazionale di Fisica Nucleare
Experimental Results On The AURIGA Optical Readout
An optical readout for the AURIGA detector is currently under development. It is based on a Fabry-Perot
optical cavity, whose mirrors form a mechanical resonator coupled to the bar. The relative motion of the
two mirrors is converted into a frequency shift of a resonant Nd:YAG laser. A second, stable Fabry-Perot
sensing cavity is used as reference for detecting the frequency fluctuations of the laser and thus the
AURIGA bar vibrations. The frequency stability of the system has been studied with the help of two equal
sensing cavities. Preliminary tests are being carried out on a system formed by a room temperature bar
equipped with the full optical readout.
POSTER
DE ROSA
F.Barone1,E.Calloni2, R.De Rosa2, L.Di Fiore3, A.Eleuteri2, L.Milano2, K.Qipiani3
1
Universita' di Salerno and INFN sez.Napoli
Universita' di Napoli Federico II and INFN sez.Napoli
3
INFN sez.Napoli
2
A Real Time Procedure for Environmental Noise Detection in GW Laser Interferometer
Interferometric antennas for gravitational wave detection require a continuous monitoring of the possible
noise sources that can have effects on the output signal. These environmental data are essential to separate
real gravitational wave events from signals coming from anomalous conditions. In this paper a real time
numerical procedure for noise uncoupling is described. A Michelson interferometer is used to test the
Amaldi 4
Abstracts
Page 13
procedure. The apparatus is equipped with an Episensor for seismic noise measurement, while a set of
microphones monitors the acoustic noise in the interferometer arms. A VME based acquisition system
collects the data from the sensors while a CPU board performs the on-line processing to uncouple the two
contributions from the interferometer output. The good agreement between the real signal and the
reconstructed one confirms the effectiveness of this technique.
FUTURE DETECTORS - Friday
DESALVO
R. DeSalvo
California Institute of Technology
Pathfinding towards Cryo-LIGO
Advanced LIGO is supposed to bring the GW interferometer sensitivity down to the best thermal noise
limit achievable with the best materials and best techniques now available. After that, there are few ways
left to get better further beat down the thermal noise: using very large test masses (of the order of a ton),
subtract the thermal noise from a reference mass, refrigerate the test masses to reduce their thermal activity.
A few groups are already active in this field. This talk will illustrate the initial path that is being taken by
LIGO scientists to explore this possibility.
RESONANT MASS DETECTORS - Friday
DE WAARD
A. de Waard, L. Gottardi and G. Frossati
LION Institute of Physics, Leiden University
MiniGRAIL, Progress Report
Results of the first cooldown of MiniGRAIL are presented. MiniGRAIL is a 65 cm diameter spherical
gravitational wave detector with a resonant frequency of around 3.1 kHz . The antenna should operate at a
temperature lower than 20 mK and have a strain sensitivity of about 10 -20. In the first run the sphere was
cooled down to 1.8 Kelvin. A forced helium flow was used to cool the sphere down to 4 Kelvin within 2
days. We measured the temperature dependence of the mechanical quality factor and made an evaluation
of the heat leaks to improve the cryogenics of the system.
OPERATING DETECTORS - Tuesday
DI FIORE
L. Di Fiore
INFN
Present Status of the VIRGO Central Interferometer
The VIRGO Central Interferometer (CITF) is a short suspended interferometer operated in the central area
of the VIRGO detector. The main motivation for building the CITF is to allow the integration and
debugging of a large part of the subsystems of VIRGO while the construction of the long arms of the
antenna is completed. This will permit a faster commissioning of the Antenna when the construction will be
completed. In fact, almost all the main components of the CITF, with the exception of the large mirrors and
few other details, are the same that will be used for the full-size detector. In the talk the present status of the
VIRGO CITF will be reviewed and some information on the next steps for the completion of VIRGO will
be given.
Amaldi 4
Abstracts
Page 14
SOURCES - Monday
DIMMELMEIER
H. Dimmelmeier, J. A. Font, E. Muller
Max-Planck-Institut fur Astrophysik
Gravitational Waves From Relativistic Rotational Core Collapse
We have performed a numerical study of rotational supernova core collapse in general relativity. The
hydrodynamic equations are formulated in a flux-conservative form and solved using high-resolution
shock-capturing methods. The Einstein equations are approximated with a conformally flat 3-metric. We
present gravitational radiation waveforms for a variety of initial conditions, and compare them to
Newtonian results. General relativistic effects especially influence rapidly rotating core collapse
configurations. The waveforms we obtain can be used as templates for gravitational wave detector data
analysis.
SPACECRAFT METHODS - Wednesday
DOLESI
R. Dolesi
LISA Drag-Free Technology
Abstract not available.
FUTURE DETECTORS - Friday
DREVER
R.W.P. Drever and S.J. Augst,
California Institute of Technology
Extension of Interferometer Operation to Low Frequencies, and Other Areas
Experiments relating to concepts for extending interferometer operation, particularly at low frequencies,
will be discussed. This includes work with coupled suspensions and other techniques.
POSTER
DUPUIS
R. J. Dupuis
University of Glasgow
Searching for Gravitational Waves from Pulsars
Known radio pulsars might be emitting gravitational waves by mechanisms such as deformations in the
crust and other asymmetries. Upper limits on the amount of gravitational radiation from these objects can
be calculated using their known properties. For the case of known pulsars the bandwidth of the expected
signal is much smaller than the detector bandwidth. Thus the data will be heterodyned and low-passed
filtered before the analysis. In order to optimize the signal-to-noise ratio from the expected quasi-sinusoidal
signal, we need to consider the Doppler shift from the rotational and orbital motion of the Earth. The
different sensitivities of the detector to the two polarizations of the gravitational radiation will cause
amplitude modulation in the signal. This complication must be addressed in an optimized search. The
results of implementing a minimum chi-square estimator are compared to a Fourier transform of a
measured signal from the Crab pulsar.
Amaldi 4
Abstracts
Page 15
OPERATING DETECTORS - Tuesday
EVANS
M. Evans
California Institute of Technology
Lock Acquisition in Complex Resonant Interferometers
Lock acquisition is the process by which an initially uncontrolled resonant interferometer is brought to its
operating point. A theoretical framework for understanding this necessary and often treacherous step on
the path to interferometer operation will be presented, along with the results of its application to the LIGO
1 2 kilometer detector.
RESONANT MASS DETECTORS - Friday
FAFONE
V. Fafone
The New Run of NAUTILUS
Abstract not available.
POSTER
FEBO
L. Iess, L. Febo, J.W. Armstrong, B. Bertotti, A. Vecchio
Universita' di Pavia
Search for Gravitational waves from coalescing binaries with the Ulysses spacecraft
A search for gravitational waves from inspiraling compact binaries have been carried out in the Doppler
data from the spacecraft Ulysses by the method of matched filtering. Using the Sathyaprakash-Dhurandar
formalism, we choose a discrete set of matched filters which approximate possible signals. Due to low
sensitivity of the experiment and the characteristics of the accessible sources, PN terms produce small
phase shifts, so that Newtonian templates are adequate. The explored region of parameter space (chirp
mass and direction of the source) has been choosen to ensure a significant SNR (larger than 5) at a distance
larger than 1 kpc. We present the results of an all-sky search and a targeted search for binaries in the
Galactic Centre.
POSTER
FINN
L.S. Finn
California Institute of Technology
Network Analysis
Abstract not available.
OPTICAL SUBSYSTEMS - Thursday
FLAMINIO
R. Flaminio
LAPP
Signal Detection System For The VIRGO Interferometer
The signal detection system consist of all the output optics and electronics necessary for the measurement
of the signal at the interferometer output. An output mode-cleaner has been developed in this context. The
system has been installed at the site and is now being used for the VIRGO central interferometer.
Amaldi 4
Abstracts
Page 16
RESONANT MASS DETECTORS - Friday
FRAJUCA
C. Frajuca and O. D. Aguiar and K. L. Ribeiro
CEFETSP
Transducers for the Braziliam GW Detector ‘Mario Schenberg’
Mario Schenberg is a spherical resonant-mass GW detector that will be part of a GW detection array of
three detectors. The other two will be built in Italy and in the Netherlands. Their resonant frequencies will
be around 3.2 kHz with a bandwidth of about 200 Hz. This range of frequencies is new in a field where the
typical frequencies lay below 1 kHz, making the transducer development much more complex. In this
presentation, the geometry of such transducer and the intermediate modes will be shown with some
preliminary results.
OPERATING DETECTORS - Tuesday
FREISE
A. Freise and the GEO 600 Team,
Institut fuer Atom- und Molekuelphysik, University of Hannover
The First Arm Of GEO 600
The first large scale optical system within GEO 600 has been realised. We have locked a pre-stabilised
laser to a 1200m long cavity embedded in one of the Michelson arms. The cavity is folded inside a 600 m
vacuum system and consists of an end mirror a folding mirror and a power recycling mirror with a
transmission of T=1.5%. The frequency stabilisation uses a chain of servo loops with two suspended mode
cleaner cavities as frequency discriminators. The achieved frequency stability at the input of the 1200m
cavity meets the GEO 600 specifications. An outline of the control scheme and its performance will be
given.
ISOLATION and SUSPENSION - Wednesday
GIAIME
J.A. Giaime
Louisiana State University
Seismic Isolation for Advanced LIGO
Abstract not available.
OPTICAL SUBSYSTEMS - Thursday
GOSSLER
S. Gossler and the GEO 600 Team
Institut f¸r Atom- und Molek¸lphysik, University of Hannover
The Mode-Cleaner System And Suspension Aspects Of GEO 600
For the stabilisation of the laser system we use two 8 m ring-cavities as a mode-cleaner system. To isolate
the cavities with respect to the seismic noise the optical components are suspended as double-pendulums.
The resonances of these pendulums are damped by a local-control loop via magnet-coil actuators acting on
the intermediate masses. The suspension scheme and the measured key data (finesse, linewidth, in-lock
time, isolation performance, frequency stability) of the mode-cleaners will be described. Furthermore we
will give an overview of the GEO 600 interferometer suspensions.
Amaldi 4
Abstracts
Page 17
RESONANT MASS DETECTORS - Friday
GOTTARDI
L.Gottardi, A. De Waard, G.Frossati
LION Institute of Physics Leiden
Preliminary Tests For A Two Mode Transducer For MiniGrail
We are developing a two mode resonant transducer for miniGrail, a 1.2 ton, 65cm in diameter spherical
gravitational wave antenna. The transducer has a first resonating mass in CuAl 6% and a second smaller
mass in Al5056. We report several quality factor measurements, down to 4K, performed on a scaled size
CuAl transducer in different conditions: when suspended from a wire and when clamped, by thermal
contraction techniques, into a hole of a sphere with a diameter of 150 mm. Q factor measurements at 4K of
a first resonator prototype for miniGrail are also presented. A design of the transducer including the
inductive read-out is discussed.
OPTICAL SUBSYSTEMS - Thursday
GROTE
H. Grote and the GEO 600 Team
Institut fuer Atom- und Molekuelphysik, University of Hannover
The Autoalignment System of GEO 600
We give an overview of the automatic mirror alignment control of the GEO 600 modecleaner- and main
interferometer. In order to achieve the required sensitivity of the interferometer, the TEM00 eigenmodes of
all optical cavities have to be aligned with respect to the incoming beams (or vice versa) and kept there for
long measuring periods. Moreover the beam spots have to be centered on the mirrors to minimize coupling
of angular mirror motion into longitudinal signals. We present the sensor and actuator designs, explain the
actual servo topology and show first results, including the error-point spectra of mirror angular motions,
which are smaller than 1e-8 radian / sqrt(Hz) below 10 Hz.
POSTER
GRUNSKAYA
L. V. Grunskaya, V. V. Isakevich, I.N. Gavrilov
Vladimir State University
The Searching Of The Correlation Between Electromagnetic Field Of The Earth In The ELF Range And
The Gravitational Wave Radiation Of The Binary Stars
The work provides using of broad possibilities of the unique experimental Vladimir University base for
making fundamental physical researches. Solving the main problem of the project, the development of the
method and means of the experimental confirmation of the existence of the interrelation effect of the ELF
electromagnetic Earth field with the gravitational wave influence from the binary stars systems with the
ELF-range of the gravitational wave radiation, a number of important results was achieved. In 1998, 1999
and 2000 on the VSU experimental ground there were done 3 research expeditions on the field
experimental investigations of the ELF electromagnetic fields. (Penkino village, Kameshkov district,
Vladimir region). According to the results of the records there were got numerous catalogues of the spectra
of the Earth field electrical and magnetic component, allowed to extract the main groups of the ELF range
signal sources in the analyzed range of frequencies, the diurnal Earth rotation and the harmonics of that
frequency, the Moon-Sun tides and the gravitational wave radiation of the binary stars systems. The work
is accomplished with the support of the Russian Fund of the Fundamental Investigations, project N 00-0579028i.
Amaldi 4
Abstracts
Page 18
FUTURE DETECTORS - Friday
HARTLE
J. Hartle
Overview Talk
Abstract not available.
CONFIGURATIONS - Wednesday
HEINZEL
G. Heinzel for the GEO 600 team
Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein Institut
Signal Recycling in GEO 600
The design and present status of dual recycling, which is an essential part of the GEO600 design, will be
presented.
RESONANT MASS DETECTORS - Friday
HENG
Ik Siong Heng
Louisiana State University
Operating ALLEGRO in the Wider Community
The Allegro resonant-mass gravitational wave detector began long term operation in 1991 and, apart from a
two year upgrade period, was continuously operating until March 2000, when it ceased operation for
laboratory renovations. During this period, it operated with an average strain sensitivity of ~7 x 10 -19 with
a minimum of 4 x 10-19 observed in 1994. As a member of the International Gravitational Event
Collaboration (IGEC), the Allegro detector group is working with the worldwide network of resonant-mass
gravitational wave detectors to search for burst gravitational waves. It is also looking collaborate with
LIGO to set upper limits on burst gravitational waves and the stochastic gravitational wave background. In
this talk, an overview of the Allegro detector and its involvement with the IGEC and LIGO will be
discussed.
POSTER
HOFFMANN
H. Hoffmann, T. Barber, J. Winterflood, D. Blair
The University of Western Australia
Vibration Isolation Systems and Seismic Waves
Low frequency vibration isolation systems can be used to measure the tilt of the ground caused by seismic
waves. Land waves are produced by ocean waves hitting to the shore. Their frequency ranges between 0.1
and 0.01 Hz. We used a Roberts Pendulum as a vibration isolator with a resonant frequency of 0.1 Hz. A
feedback control system was used to compensate for the long term drifts of the pendulum. These drifts are
probably caused by temperature gradients between the wires of the pendulum. A very low frequency
analogue integrator based on a Supercap capacitor is shown to be a simple way to compensate for the drifts.
POSTER
HUELLER
M. Hueller
University of Trento & CCR
Torsion Pendulum Facility for Ground Testing of Inertial Sensors for LISA
Mauro Hueller (1,2), Antonella Cavalleri (3), Rita Dolesi (1,2), William
Amaldi 4
Abstracts
Page 19
Weber (1,2,4), and Stefano Vitale (1,2,4)
1. Universita' di Trento, Dipartimento di Fisica
2. Istituto Nazionale di Fisica Nucleare (INFN)
3. Centro Fisica degli Stati Aggregati (CEFSA)
4. Consorzio Criospazio Ricerche (CCR)
In this poster we report on a ground-based torsion pendulum test facility for LISA inertial sensors. We aim
to measure weak forces exerted on a test mass suspended from a thin torsion fiber, inside a LISA prototype
capacitive position sensor. The ultimate limit on the force sensitivity of the proposed torsion pendulum is
fixed by intrinsic thermal noise at 5 10-13 N / Hz1/2. The facility will permit measurement of the electrostatic
coupling between the test mass and sensor, evaluation of the electrostatic suspension system needed for
LISA at very low frequencies, and characterization of other weak forces relevant to LISA drag free control.
We describe here the design and implementation of the apparatus, its expected performance, and some
preliminary measurement results.
POSTER
IBRAHIM
N.Ibrahim and Y.T.Chen
Univ. Teknologi Malaysia
Present Work On Gravitational Wave Detection In Malaysia
The relocation and reassembling of 100m laser interferometer from Institute of Space and Astronautical
Sience, Japan to Univetsiti Teknologi Malaysia in Johor Bahru, Malaysia was successfully undertaken in
mid 1997. Since then, we have begun to restore and increase the sensitivity of this Michelson type laser
interferometer. This papaer gives an overview of the progress on the interferometer including the optical
set-up, site location, ground noise and delay-line performance. Few possibilities are proposed for the future
improvements including folded optical arms, a combination between Fabry-Perot and Michelson type
interferometers.
FUTURE DETECTORS - Friday
INGLEY
A.M. Cruise and R.M.J. Ingley
University of Birmingham
An Electromagnetic Detector for High Frequency Gravitational Waves
There are sound reasons to believe that cosmological stochastic backgrounds may have been generated in
the very early moments of the Universe by parametric amplification of quantum fluctuations. The exact
spectrum will depend strongly on the details of the inflation entry and exit and but recent predictions
suggest peaks in the spectrum at frequencies of several hundred MHz or higher. This range is too high to
consider detectors based on moving masses and therefore direct (or indirect) interactions between
electromagnetic and gravitational waves are possible mechanisms. One of these interactions causes a
rotation of the plane of polarisation of the electromagnetic wave when in the presence of a gravitational
wave. Recent studies have shown that a resonant effect can be used to enhance the rotation linearly under
particular conditions. A laboratory prototype of such a detector is in operation at Birmingham and the talk
will describe its properties and potential development.
POSTER
IVANOV
M.A. Ivanov
Belarus State University of Informatics and Radioelectronics
Non-Dopplerian Cosmological Redshift Parameters In A Model Of Graviton-Dusty Universe
Possible effects are considered which would be caused by a hypothetical superstrong interaction of photons
or massive bodies with single gravitons of the graviton background. If full cosmological redshift
magnitudes are caused by the interaction, then the luminosity distance in a flat non-expanding universe as a
function of redshift is very similar to the specific function which fits supernova cosmology data by Riess et
Amaldi 4
Abstracts
Page 20
al. From another side, in this case every massive body, slowly moving relatively to the background, would
experience a constant acceleration, proportional to the Hubble constant, of the same order as a small
additional acceleration of Pioneer 10, 11.
POSTER
IZMAILOV
G.N. Izmailov
Moscow State Aviation Institute (Technical University)
Can we use LISA for the Hubble constant measurement?
An analysis of possibilities of the Hubble constant measurement is presented. It is shown that there are
technical problems to gauge the constant. Estimates of the necessary accuracy are included.
POSTER
IZMAILOV
G.N. Izmailov, D.V. Malugin, V.V. Ozolin
Moscow State Aiation Institute (Technical University)
Wireless Data Control And Acquisition Set-Up
There is a problem of eliminating of a back action of an acquisition system on a transducer in precisionn
experiment such as a gravitation wave detection. One uses a wireless communication between a transducer
and a detector as a rule. A bilateral set-up for a date control and aquisition is described. It was designed for
the date acquisition and control of an experimental equipment installed on a movable platform and trans
mitting signals in a IR frequency range.
SPACECRAFT METHODS - Wednesday
JENNRICH
O. Jennrich
University of Glasgow
Optics for LISA
Some work for optics on LISA has been done in conceptual studies for optical layouts for technology
demonstrator missions. Although not primarily designed for interferometry, some key issues of the LISA
optics, i.e. phase measurement, can be addressed. An possible optical layout has been set up as a table top
experiment and has been used to demonstrate a method of measuring the phase of laser light suitable for
use in LISA. A method of attaching optics to a zerodur optical bench has been tested. This method, known
as silicate bonding was developed for space missions and has proven its reliability in vibration tests. Two
different ways of retrieving the phase of laser light with respect to a local oscillator will be presented.
SOURCES - Monday
JONES
D. I. Jones
University of Southampton
Gravitational Waves From Neutron Stars
In this talk I will review gravitational wave emission from `deformed' rotating neutron stars. By deformed
I mean that the equilibrium shape of the star is not simply determined by gravity, rotation and fluid
pressure, but is instead due in part to some other force, such as strain in a solid crust, or a magnetic field. I
will describe the frequency of gravitational wave emission from such stars, including the case of free
precession. Finally, and most importantly, I will examine a number of realistic astrophysical scenarios in
which such radiation might be produced, and estimate the likely wave amplitudes.
Amaldi 4
Abstracts
Page 21
ISOLATION and SUSPENSION - Wednesday
JU
L. Ju, D. Paget, D. G. Blair
Department of Physics, The University of Western Australia
High Q Sapphire Test Mass Suspension With Niobium Membrane Flexure
Niobium membrane flexure suspensions has been proved to be able to achieve high pendulum Q-factor,
while niobium cantilevers suspension has been proved to give high internal Q factors of sapphire test
masses. Here we present results of sapphire test mass suspension systems based on the use of niobium
flexures. A suspension module consisting of membrane flexure combined with small cantilevers have been
developed. This suspension system has the advantage of being robust while maintaining the high Q of the
sapphire test mass.
LASERS and OPTICS - Thursday
KELLS
B. Kells
California Institute of Technology
In Situ Characterization Of LIGO Optics
The two kilometer LIGO I interferometer has now been fully operated at low laser beam power. Direct
measurement of the performance of this resonant locked system has allowed some preliminary conclusions
as to the quality of the LIGO I core optics. We present and interpret these measurements with respect to
the anticipated performance based on optic fabrication acceptance metrology. The consistency of the
various observations will be discussed. Prospects for complete characterization of the interferometer optics
during
the present commissioning phase of operations will be outlined.
OPERATING DETECTORS - Tuesday
KOETTER
K. Koetter and the GEO 600 team,
Institut fuer Atom- und Molekuelphysik, University of Hannover
Detector Characterization Of GEO 600
The data acquisition system of the gravitational wave detector GEO600 is recording the first data now.
Data from detector subsystems and environmental channels is being acquired. First result from the analysis
of the interaction between subsystems will be presented. Transfer functions have been measured to
determine noise propagation in the detector. We also analysed environmental influences on the detector.
Long term monitoring allowed us to assess and improve the reliability of the subsystems.
POSTER
KLIMENKO
S.Klimenko, G.Mitselmakher, A.Sazonov
University of Florida
Wavelet Analysis of Data from Gravitational Wave Interferometers
Wavelets are widely used in signal and image processing. We describe applications of wavelets for analysis
of data from GW interferometers, including data compression, detection and identification of transients
(detector artifacts) and detection of signals from unmodeled GW sources (like bursts) where match filtering
technique can't be used.
We have developed lossless and lossy data compression based on wavelets. Lossless compression is based
on the lifting wavelet transform that maps integers to integers. The wavelet transform works in
combination with the random data compression encoder that is optimized for compression of random
Amaldi 4
Abstracts
Page 22
Gaussian signals. For lossy compression the lifting and Daubechie's wavelets are used in combination
with the data dynamic range reduction, that introduces a small amount (~1%) of colored Gaussian noise to
the data. Lossy compression allows considerable reduction (~1/10) of amount of data, that could be as large
as 1TB/year (LIGO experiment), without introducing significant artifacts. Wavelet compression can be
used to generate reduced data sets and it is very flexible to accommodate a wide range of data analysis
tasks. Wavelet allows time-scale (frequency) representation of data.
We use shrinking of wavelet
coefficients and pattern recognition in time-scale domain to build wavelet filters for detection of relatively
short signals (like bursts) with unknown (or poorly known) waveform. Although this kind of filter is
sensitive to all kinds of background signals (like transients), it allows to build banks of events of interest.
The event banks can be used to study transients and for the GW bursts data analysis.
POSTER
KONOPLYA
R. A. Konoplya
Dnepropetrovsk State University
Quasinormal Modes Of The Electrically Charged Dilaton Black Hole
We have computed the quasinormal modes of the electrically charged dilaton black hole. At the earlier
stage of evaporation (Q is less than 0.7-0.8 M), the dilaton black hole "rings" with the frequencies which
differ negligibly from those of the Reissner-Nordstrom black hole. The QN spectrum of frequencies weakly
depends on the dilaton coupling. The real part of the frequencies and the damping time for the dilaton black
hole is less than those of the Reissner-Nordstrom black hole with the same electric charge. It can easily be
explained by the fact that the scalar (dilaton) field contributes an extra attractive force which compensates
partly the effect from the increased electric charge thereby stipulating "retarding" in growing of the
frequency when increasing the electric charge. As is known the frequencies for the electromagnetic and
gravitational perturbations coincide in the extremal limit for the Reissner-Nordstrom BH (Onozawa, 1997),
supporting the fact that only the exremal black hole is supersymmetric. This is not the thing for the
electrically charged dilaton black hole. Apparently, one should expect that the extremal dilaton black hole
with both electric and magnetic charges, being N=4 supersymmetric when embedded in N=4 supergravity,
will respond in the same manner on the electromagnetic and gravitational perturbations. The bulk of our
work concerns the a=1 dilaton black hole which is suggested by the low-energy limit of superstring theory.
POSTER
KONOPLYA
R. A. Konoplya
Dnepropetrovsk State University
Quasi-normal modes of string analog of R-N black hole
We find the spectrum of quasi-normal frequencies for analogue of Reisner-Nordsterm non-extremal black
hole in string theory. It proves out that the spectrum of frequencies is considerably lower than that of the
classical R-N, black hole. Due to presence of the dilaton field the spectra for axial and polar modes are
different. The complex part of the basic frequency for a given charge is roughly proportional to the black
hole temperature at lest when the black hole is large macroscopic object.
POSTER
KURBANOVA
V. Kurbanova
Kazan State University, Russia
World-line deviation in the systems with hidden interactions in the gravitational wave background
Basing on the Synge's theory of geodesic deviation and its extension to the case of deviation of world lines
of charged particles (Balakin, van Holten and Kerner, CQG, Dec.2000), the generalization of the theory of
deviation was made. From the classical theory the present one is distinguished by:
Amaldi 4
Abstracts
Page 23
* introduction of an additional vector field describing polarization or spin of a particle, determined along
all world-line for each particle and depending on two parameters, parameter along the trajectory and
parameter which counts trajectories;
* presence of forces in the right part of the equations of dynamics. Among these forces tidal and
electromagnetic forces effecting vector bozons and spin particles are considered.
The exact solutions of the systems of equations describing world-line deviation for these cases in the
background of the plane gravitational wave were found.
OVERVIEWS - Monday
KURODA
K. Kuroda and LCGT Collaboration:
ICRR-The University of Tokyo, National Astronomical Observatory, High Energy Accelerator Research
Organization, Physics Department-The University of Tokyo, Department of advanced materials scienceThe University of Tokyo, ILS-University of Electro-Communications, ERI-The University of Tokyo,
Miyagi University of Education, Metrology Institute of Japan, Department of Earth & Space Science-Osaka
University, YITP-Kyoto University, Physics Department-Niigata University
Japanese Large Interferometer -TAMA and LCGT
The objective of the TAMA 300m interferometer is to develop advanced technologies for a km scale
interferometer and to observe possible gravitational wave events in nearby galaxies. It is designed as a
power recycled Fabry-Perot Michelson interferometer and is positioned as a step for the final
interferometer in Japan. The funding originally covered five years construction including short term
operation. We began its construction in April of 1995. Its first operation was done in February of 1999.
Two years extension was approved last April. Although the power-recycling mirror has not yet been
installed (Phase I), noise hunting is successfully being done and the power recycling mirror will be installed
soon.
The sensitivity of TAMA is approaching its goal of Phase I, which is the most sensitive gravitational wave
detector in the world in June, 2001. After taking the long series of data over 160 hours last autumn, we
applied two major improvements with several minor changes for higher sensitivity. They were: 1)
installation of an active pneumatic isolation system and 2) decreasing the pitching motion of the mirror
suspension with an improved alignment control feedback system. These improvements have made the
sensitivity higher and have also made daytime operation of the interferometer possible. Recent operation
has shown 24 hours continuous locking, which is the world’s longest record for this size of interferometer.
We are now replacing a mode matching telescope of refractive type with a reflective one in order to reduce
stray light preventing us from reaching shot noise sensitivity. We plan to take longer data (more than 1000
hours) in this summer.
This effort on TAMA becomes a basis of LCGT, which is a 3km scale cryogenic interferometer built in the
mine of Kamioka, with techniques developed for cryogenic mirrors. The revised plan of LCGT and
activities for LCGT are also introduced in the talk.
OPTICAL SUBSYSTEMS - Thursday
LANDY
M. Landry
LIGO, Caltech
LIGO Sensing System Performance
A brief description of the LIGO length and alignment sensing and control systems will be followed with a
status report on their performance to date.
Amaldi 4
Abstracts
Page 24
POSTER
LANGE
B. Lange
Drag-Free Performance In a LISA Mission with Spherical Proof Masses
The drag-free performance of a LISA satellite using a single spherical proof mass reflecting two light
beams at a 60-degree angle is discussed. Using a spherical proof mass has a number of advantages: no
forces or torques are deliberately applied to the proof mass, the drag-free performance can be guaranteed
from the DISCOS results combined with the expected performance of modern drag-free controllers, a
special technology mission would not be needed to demonstrate the drag-free performance, and the system
is completely drag-free even though the reference directions are at 60 degrees rather than 90 degrees.
ISOLATION and SUSPENSION - Wednesday
LA PENNA
A. di Virgilio, P. La Penna
INFN Sezione di Pisa
Status of the LFF Experiment
The LFF (Low Frequency Facility) is an R&D experiment aimed to measure the thermal noise of the Virgo
suspensions. It consists of a complete attenuation chain, to which, instead of a single mirror, a short (1 cm),
two mirror, high finesse (more than 1000) optical cavity is suspended. The cavity is kept resonant on a
Nd:Yag laser beam by means of the Pound-Drever technique. The fluctuations of the cavity length is
measured using the demodulated reflected beam. The small length of the cavity is designed in order to
minimize the effects of frequency fluctuations of the laser, which is further frequency stabilized by locking
it to a ULE reference cavity. The present status and the first results of the experiment are presented: the SA
is placed in vacuum, the cavity is suspended, the optical input bench is ready and the input light beam is
provided.
POSTER
LAZZARINI
A. Lazzarini and L. S. Finn
California Institute of Technology
A Technique For Modulating The Experimental Signature Of A Cosmic Gravitational Wave Background.
Detecting a stochastic gravitational wave signal is complicated by the inability of observing the detector
noise independently of the signal. One consequence is that at least two detectors are required to observe a
signal as a cross-correlation between detector outputs. A second consequence is that there can remain a
systematic error, associated with the possible presence of correlated instrumental noise, in any observation
aimed at estimating or limiting a stochastic gravitational wave signal. We discuss a method to identify
systematic errors by varying the orientation of one detector relative to the other, providing separate and
independent modulations of the signal and noise contributions to the cross-correlation. We analyze the
method for detecting a stochastic signal with the ALLEGRO and LIGO Livingston detectors.
POSTER
LEONHARDT
V. Leonhardt, L. Ribichini, P. Klvekorn, H. LUck, K. Danzmann
Institut fur Atom- und Molekulphysik
University of Hannover
Towards measuring the off-resonant thermal noise of a pendulum mirror
Thermal noise is one of the dominant noise-sources in interferometric-length measurements and therefore
can limit the sensitivity of gravitational-wave detectors. Thermal noise can be analysed by
interferometrically detecting the length-changes of an optical cavity, which consists of two mirrors
Amaldi 4
Abstracts
Page 25
suspended independently as multiple stage pendulums. Further seismic isolation and a stabilisation of the
laser-frequency is also necessary. We present the set-up of such an experiment and some preliminary
results.
POSTER
LESHANU
C. Leshanu
Kiev University
Hole Teleportation By Closed Gravity Field
Teleportation of body to any point in the universe, by first placing it outside of universe. For teleportation
we must create the geometry similar to a black hole by help of closed gravitational field.
ISOLATION and SUSPENSION - Wednesday
LIBBRECHT
K.G. Libbrecht
California Institute of Technology.
The Thermal Noise Interferometer at Caltech
This talk will give an update on the Thermal Noise Interferometer (TNI) experiment at Caltech. The TNI is
a suspended interferometer using short arm cavities with high-finesse mirrors, aimed at making
measurements of the details properties of many types of displacement noise, especially thermal noise and
excess (non-Gaussian) noise, in fused silica and sapphire mirrors. The TNI recently achieved "first lock",
and we expect to have preliminary noise spectra in the near future.
SOURCES - Monday
LINDBLOM
L. Lindblom
Caltech
Relativistic Instabilities in Compact Stars
The emission of gravitational radiation (GR) can drive an instability in certain modes of rotating stars. This
process may play an important role in the evolution of rapidly rotating neutron stars, and the emitted by this
mechanism may become detectable by the laser interferometer GR detectors now under construction. I will
discuss at a pedagogical level the mechanism that drives this instability, our current understanding of the
role this instability may play in real astrophysical neutron stars, and the strength and character of the GR
that may be emitted as a result of this instability.
FUTURE DETECTORS - Friday
LOBO
A. Lobo
University of Barcelona
Hollow Sphere: A Flexible Multimode GW Detector
Hollow spheres have the same theoretical capabilities as the usual solid ones, since they share identical
symmetries. The hollow sphere is however more flexible, as thickness is an additional parameter one can
play with to approach given specifications. I will briefly discuss the more relevant properties of the hollow
sphere as a GW detector (frequencies, cross sections), and suggest some scenarios where it can be useful.
Amaldi 4
Abstracts
Page 26
ISOLATION and SUSPENSION - Wednesday
LOSURDO
G. Losurdo
INFN Florence
Active Controls Of The VIRGO Superattenuator
The VIRGO SA has been designed in order to implement a hierarchical control of the mirror position. The
control forces are exerted on 3 points along the chain: the suspension point (via a soft inverted pendulum),
the marionette (an intermediate mass suspending the mirror) and the mirror (via a seismic noise free recoil
mass). On the IP a multi d.o.f. control of the SA DC position and of the SA resonances (inertial damping) is
implemented, aimed to reduce the rms motion of the mirror down to ~1 micron. The results are presented
and discussed.
RESONANT MASS DETECTORS - Friday
MAGALHAES
R. M. Marinho, Jr. (Technological Institute of Aeronautics, Brazil)
N. S. Magalhaes (Bandeirante University, Brazil)
O. D. Aguiar (National Institute for Space Research, Brazil)
Universidade Bandeirante de Sao Paulo
Response Of Spherical Gravitational Wave Antenna Modes To High Energy Cosmic Ray Particles
High energy cosmic ray particles are expected to be a significant source of noise in resonant mass
gravitational wave detectors close to the quantum limit. The spherical, fourth generation antennas is
expected to attain such limit. In this presentation we will show how the energy of a cosmic ray particle
interacting with such an antenna is distributed over its eigenmodes. We will then make some comments on
relevant consequences of such distribution to gravitational wave detection.
POSTER
MARIN
A. Marin1, M. Bignotto1, M. Bonaldi2, M. Cerdonio1, P. Falferi2, R. Mezzena3, G. A. Prodi3
G. Soranzo1, L. Taffarello1, A. Vinante3, S. Vitale3, J.-P. Zendri1
1
Dipartimento di Fisica, Università di Padova and INFN
Sezione Padova Via Marzolo 8, I-35100, Padova, Italy
2
Centro di Fisica degli Stati Aggregati CNR-ITC and
INFN Gruppo Coll. Trento I-38050 Povo (Trento), Italy
3
Dipartimento di Fisica Università di Trento and INFN
Gruppo Coll. Trento, I-38050 Povo (Trento) Italy
Noise Measurement and Optimization of the High Sensitivity Capacitive Transducer of AURIGA
The main goal of the next cryogenic AURIGA run is to open up the detection band to at least 30 Hz while
maintaining a peak strain sensitivity of 4*10^(-22)/Sqrt(Hz). In order to obtain this there will be some
important modifications on the apparatus. The first one will be the use of a heavier capacitive transducer
(about 3 Kg of effective mass); the second one will be the tuning of the high Q (above 1 million) electrical
mode to the mechanical modes of bar and transducer. The electrical mode is constituted by the transducer
capacitance and by the inductance of the primary coil of the matching transformer. The last difference is
the use of a low noise two-stage SQUID system (about 200 h-bar) as signal amplifier. The experimental
tests performed so far were all done in the AURIGA Ultracryogenic Test Facility (TF). The mechanical
isolation system (about 180 dB at 1 kHz) and the cryogenics of the TF are showed. The measures
performed on the High Sensitivity Capacitive Transducer are presented, with the foreseen sensitivity curve
for the second AURIGA run.
Amaldi 4
Abstracts
Page 27
ISOLATION and SUSPENSION - Wednesday
MARKA
S. Marka, M. Ando, A. Bertolini, G. Cella, R. DeSalvo, M.Fukushima, S. Kawamura, K. Numata, V.
Sannibale, K. Somiya, R. Takahashi, A. Takamori, H. Tariq, K. Tsubono, J. Ugas, N. Viboud, H.
Yamamoto, T.Yoda, C. Wang
California Institute of Technology
Seismic Attenuation System for TAMA300 (TAMA SAS): Prototype
Our Seismic Attenuation System (SAS) was developed to provide the extremely high level of seismic
isolation required by the next generation of interferometric gravitational wave detectors. It is very likely
that extremely sensitive experiments in other fields will also profit from our work. Our aim was to provide
the best performance at low frequencies (below 100 Hz) while utilizing passive subsystems as often as
possible. The active feedback is relegated below 6 Hz and it is used to damp the attenuation chain rigid
body mode resonances and it leads to extremely low mirror residual motion. I will give an overview of the
subsystem and prototype characterization results, which strongly support our claims of excellent
performance achieved with a fundamentally passive and low cost system.
POSTER
MARKA
S. Marka and B. Mours
California Institute of Technology
Network Data Analysis Server (NDAS) Prototype
We are developing a simple and robust system utilizing standard unix tools and frame library code to
transfer and merge data from multiple detectors. The merge takes place with less than 20 minutes delay and
the output frames are available for all participants. Presently VIRGO and LIGO participate in the exchange
and only environmental data is shared. The system is modular to allow future improvements and the use of
new tools like Grid tools from Globus.
CONFIGURATIONS - Wednesday
MCCLELLAND
D. McClelland
Chair, ACIGA, The Australian National University
ACIGA: Toward A Future Southern Hemispshere Laser Interferometer Gravitational Wave Detector
The Australian Consortium for Interferometric Gravitational Astronomy (ACIGA) is developing
technology for future generations of gravitational wave detectors. in this talk I will briefly review our
activities and postulate on their incorporation into a detector in the southern hemisphere in the future.
POSTER
MELEK
M. Melek
Astronomy Department, Faculty of Science, Cairo University.
On the Sole Influence of Plane Gravitational Waves on the Magnitude of the Gradient of a Scalar Field
The sole influence of plane gravitational waves (PGW) on the magnitude of the gradient of a scalar field
(MGSF) defined inside a medium, is calculated. This study is based on a function which is defined to be
used as a measure of the temporal variation of MGSF which has a chance to be exposed to PGW. The
conditions on the relations between the fluctuations in the gradient of the scalar field (GSF) and the PGW
leading to increasing or decreasing GSF; due to the sole influence of PGW; are given. Two special cases of
laser interferometers and bar detectors are presented as an application of such approach.
Amaldi 4
Abstracts
Page 28
POSTER
MERKOWITZ
S. M. Merkowitz
NASA/GSFC
The LISA disturbance reduction system
The success of the LISA project depends on the ability of the disturbance reduction system to shield the
proof mass from all external forces. I will present the results of a drag free control analysis that tests the
feasibility and practical requirements of the disturbance reduction system. In addition, I will present the
status of our microNewton thrust-stand that will verify that the thrusters proposed for LISA will meet the
LISA noise requirements.
SOURCES - Monday
MILLER
M. Miller
Washington University
Towards the Innermost Stable Circular Orbit of the Binary/Neutron Star System/Black Hole
Only a full 3D general relativistic numerical calculation will be able to accurately reveal the details of the
orbiting black hole / neutron star (BH/NS) system just before and during the plunge and coalescence
phases. One interesting feature of this system is the location of the innermost stable circular orbit (ISCO).
In order to begin numerical studies, one must have a reasonable place to start, namely, initial data that
satisfies the constraints of general relativity that corresponds to a black hole and neutron star in quasicircular orbit about each other, close to the ISCO. By studying constant baryon, constant black hole mass
sequences of BH/NS initial data sets in quasi-equilibrium that satisfy the constraints of general relativity,
we find approximations to the ISCO of the BH/NS system which will be used as initial data for general
relativistic numerical calculations. Preliminary results from numerical evolutions of these initial data will
is also presented.
ISOLATION and SUSPENSION - Wednesday
MIO
N. Mio
University of Tokyo
Application Of High-Performance Damping Metal To Gravitational Wave Detectors
An application of high-performance damping metal, called M2052 (Mn-based alloy with 20% Cu, 5% Ni
and 2% Fe) to gravitational wave detectors is discussed. A typical Q-value of a mechanical oscillator with
a M2052 spring is 30; this is quite small compared with an ordinary metal spring. This damping
performance can be useable in vibration isolation system of gravitational wave detectors. In particular, by
using this metal, it is possible to reduce some bad effects caused by spurious resonance modes of
supporting structures. The mechanical property of M2052 and the performance of an all-metal vibration
isolation system made of M2052 will be presented.
FUTURE DETECTORS - Friday
MITROFANOV
V.P.Mitrofanov, N.A.Styazhkina, K.V.Tokmakov
Moscow State University
Test Mass Damping Associated With Electrostatic Actuator
Electrostatic actuators are supposed to be used to provide fine control of the test mass position in
interferometric detectors of gravitational waves. The actuator can be a source of the fluctuating force acting
on the test mass due to additional damping caused by electric field of the actuator. The most important loss
mechanisms are associated with surface of metal electrodes of the actuator as well as with the fused silica
Amaldi 4
Abstracts
Page 29
test mass surface. The first one may be caused by electron transitions between local surface states in the
oxide and adsorbed layers or polarization of these layers under the action of the electric field. The surfaceadsorbed water plays the crucial role. The electrodes coated by gold were found to provide minimal losses.
The flame treatment of the fused silica test mass surface allowed us to reduce significantly the losses
associated with the test mass surface. The damping caused by electric field of the actuator is frequency
dependent. It decreases with increasing of the frequency of mechanical oscillation or the frequency of ac
electric field used in the actuator. Results of our experiments show that the damping of the test mass
oscillation associated with the multistrip electrostatic actuator can be made lower than the lowest damping
measured up to now in the pendulum mode of a prototype fused silica test mass suspension.
CONFIGURATIONS - Wednesday
MIYAKAWA
O. Miyakawa
Institute for Cosmic Ray Research, Tokyo University
Development Of RSE Interferometer Using 3rd Harmonic Demodulation
The most difficult point of RSE experiment is to extract of the signal extraction cavity with good signal
ratio. In our experiment, the signal extraction cavity will be locked by using 3rd harmonic demodulation
with big asymmetry which is adjusted to make dark condition of 3 rd order sideband in anti symmetric port.
This method has a good signal mixture ratio between arm cavity motion and signal extraction cavity
motion. We will report a present status of our bench top RSE experiment in Japan.
POSTER
MOFIZ
U. A. Mofiz and T. Tajima
Bangladesh Open University
Electromagnetic Jet from a Black Hole
Electromagnetic waves around a Kerr black hole is studied. MHD equations for black hole plasma is
considered. Gravitational dragging is found to generate a strong electromagnetic jet near the event horizon
of the black hole.
POSTER
MOHANTY
S. D. Mohanty,
Albert Einstein Institute
False Dismissals Vs False Alarms: Issues In Coincidence Detection
We present an analytic investigation of false dismissal versus false alarm probability of coincidence based
detection strategies being used currently. The effect of time of arrival estimation error (including bias) is
explicitly taken into account and it is found that in some cases, especially for GW burst detection, this can
have important consequences for the detectability of signals. Monte Carlo simulations of coincidence
detection by Finn (2000) show an asymptotic value of < 1 for detection probability as the false alarm
probability approaches infinity. We show that this arises from the mixing of detection (threshold
dependent) and estimation (threshold independent) that is inherent in a coincidence scheme. We present a
scheme for calculating the optimum window size given a false alarm rate and time of arrival estimation
error for the case of two identical, independent detectors.
Amaldi 4
Abstracts
Page 30
POSTER
MOHANTY
S. D. Mohanty,
Albert Einstein Institute
Model Independent and Transients resistant removal of multiple Narrowband noise features from
interferometric data
Removal of narrowband noise features that are of known instrumental origin is proving to be important for
several reasons, for instance: Tracking noise floor changes and Stochastic Background detection. We
present a method for removing lines which is (i) not based on any model for the amplitude and phase
modulation of the lines, (ii) works in the time domain and (iii) does not affect short duration transients in
the residual left after line removal. Property (i) allows lines to be removed from anywhere in the frequency
band, (ii) means that there are no jumps in the evolution of the line estimate and (iii) means that not only do
transients remain untouched but also that the line estimation is not affected by transients.
POSTER
MOHSENI
M. Mohseni
Payame Noor University
Spinning Particles And Gravitational Waves
The motion of a spinning particle in the field of a weak plane gravitational wave is studied in both Dixon's
and Tulczyjew's descriptions of spinning particles. It is found that for particles initially at rest they agree in
the evolution of the spin but predict slightly different orbits. This difference is due to the contribution from
the component of the spin in the direction of the wave propagation.
LASERS and OPTICS - Thursday
MUDGE
D. Mudge, M. Ostermeyer, P.J. Veitch, J. Munch, M.W. Hamilton
Adelaide University
High Power Nd:YAG Lasers Using Stable/Unstable Resonators
Lasers that use unstable resonators offer the advantages of large mode volumes, efficient energy extraction,
good mode discrimination and good beam quality at high powers. They can also beinjection-locked to
produce a single frequency output. Thus, an injection locked, unstable resonator, Nd:YAG laser appears to
be an ideal source for advanced long-baseline interferometers. The design and operation of a powerscalable diode-laser-pumped CW Nd:YAG zigzag slab laser that uses a stable-unstable resonator with a
graded reflectivity mirror as an output coupler is presented. Control of the thermal lensing in the unstable
plane is demonstrated, allowing operation of an injection locked standing-wave stable-unstable resonator
with excellent beam quality. Current efforts to demonstrate the power scalability of the laser head will be
reported.
LASERS and OPTICS - Thursday
MUELLER
G. Mueller
University of Florida
Thermal Effects in Faraday Isolators and Modulators
Abstract not available.
Amaldi 4
Abstracts
Page 31
FUTURE DETECTORS - Friday
MUELLER
G. Mueller
University of Florida
The X-coupled Interferometer
I will discuss the latest results on the cross-coupled interferometer. This type of interferometer is an
extension of a dual recycled cavity enhanced Michelson interferometer. It uses folded arm cavities and
partly transmissive end test masses. The transmitted arm cavity fields are coupled via an additional cavity
formed between the two end test masses and a new partly transmitting corner mirror. The signal will be
detected behind this mirror. The signal recycling mirror should be non transmissive to avoid any loss of
signal through the dark port. Although the shot noise limited sensitivity of this setup is very similar to a
LIGO-II type detector, it has a few other advantages: Tunability from broad band to narrow band with
variable peak frequency without changing any mirror. Less sensitive to laser noise and better sensitivity at
higher frequencies.
POSTER
MUKHERJEE
S. D. Mohanty and S. Mukherjee
Max Planck Institut fur Gravitationsphysik
Coincidence Analysis Without Fixed Window Size
In many coincidence detection problems, the coincidence window size is uncertain. For example,
coincidence between (i) Astronomical events and GW events, (ii) GW burst events in two interferometers
with coarse timing and (iii) events in auxiliary channels of an interferometer. Mukherjee and Mohanty
(Amaldi Proc., 1999) introduced a Maximum Likelihood based approach to coincidence analysis which
allows one to treat the window size as a parameter of the search along with the background and source
rates. The computation of the likelihood was found to be intractable in some situations preventing a scan
over a wide range of window sizes. A reformulation of the problem in terms of the theory of Markov
Processes is presented which extends the likelihood calculation to interesting regimes. We report results
for several different scenarios for source, background rates and window sizes. The fundamentally new
Markov process approach can be a basis for deeper investigations into other aspects of coincidence
analysis.
POSTER
MUKHERJEE
S. D. Mohanty and S. Mukherjee
Max Planck Institut fur Gravitationsphysik
Detector Characterisation Helper Robot.
A Change of non-astrophysical origin in the detector state or in the statistical nature of data while an
interferometer is in lock reflects an abnormality. The change can manifest itself in many forms: transients,
drifts in noise Power Spectral Density, change in cross-correlation between channels etc. We advance the
idea of a software tool for detecting such change points whose design goal is reliable performance, that is a
known false alarm rate, even when statistically unmodelled data such as the physical environment
monitoring channels are included. Reliability is important since following up on such change points could
be fairly labour intensive. Such a tool cannot simply be a collection of independent monitors running in
parallel and data flow through the tool need not be straightforward. We present the first design steps
towards building this Detector Characterisation Robot along with some preliminary results and outline
some possibilities for the future.
Amaldi 4
Abstracts
Page 32
POSTER
NOSKOV
V. Noskov
Institute of Continuous Media Mechanics
Electromagnetic Red Shift In The Model Of Enclosed Spaces: Possibilities Of Experimental Verification
The model of enclosed spaces (MES) is a new metrical space-time model based on the relativistic variant of
Finslerian geometry. Model and its geometry have a sufficient completeness for geometrization of
electrodynamics and mechanics of physical systems whose states depend on coordinates and velocities of
matter.
This paper is concentrated on the two predictions made in framework of MES. The first is the geometrical
restriction on the vacuum value of the scalar charged massive field of distributed matter which physically
means that dark matter hypothesis should not be necessarily used in cosmology of MES. The second
prediction is the existence of electromagnetic red shift effect, which in the MES vacuum is linear in the
electromagnetic field like a gravitational effect. The sign of the effect must be defined experimentally.
Although this effect is very weak, there are two experimental possibilities for shift verification. It can be
observed in Paund-Rebbka type laboratory experiment with Messbauer's silver nucleus and in electric field
slowly varying with time (to separate gravitational effect) with (10 - 100)kv amplitude. The other
possibility can be realized by using LIGO-type laser interferometer for observation of gravitational waves.
ISOLATION and SUSPENSION - Wednesday
NUMATA
K. Numata, S. Otsuka, M. Ando, K. Tsubono
University of Tokyo
Intrinsic Losses Of Various Kinds Of Fused Silica
We have developed a novel method that enables us to directly investigate an intrinsic mechanical loss of
bulk sample. The fundamental of this method is nodal support technique. Using this method, we measured
intrinsic losses of various kinds of fused silica that are used for interferometric gravitational wave detectors
in the world. The method and the results of the measurements will be presented in this talk.
DATA ANALYSIS - Tuesday
ORTOLAN
A. Ortolan for the AURIGA Collaboration
INFN – Laboratori Nazionali di Legnaro
Parametric Adaptive Filtering And Data Validation In Bar GW Detectors
We report on our experience in estimating signal and noise of the resonant GW detector AURIGA. Signal
is modelled as a broad band GW burst with no structure within the bandwidth of the detector and its
amplitude and arrival time ( sec accuracy) are estimated with a matched-adaptive Wiener filter. The
detector noise, entering in the filter set up, is modelled as an 8 parameters AR(4)MA(4) process. To
account for some slow non-stationarieties of the noise, the ARMA parameters are estimated hourly. A
crucial point in setting up the correct Wiener filter is the separation of time spans with “almost Gaussian”
noise from non-Gaussian and/or strongly non-stationary ones. The separation algorithm consists basically
of a variance estimate with the Chauvenet convergence method and a threshold on the Curtosis index. The
validation of data is strictly connected with the separation procedure: by injecting a large number of
artificial GW signals in the “almost Gaussian’ part of the AURIGA data stream, we have demonstrated that
the effective probability distributions of signal-to-noise ratio, chi-square and time of arrival are the
expected ones.
Amaldi 4
Abstracts
Page 33
POSTER
PAGET
D. Paget, Ju L., J. Winterflood, D. Blair
Department of Physics, The University of Western Australia
Improved Technique For Measuring High Pendulum Q Factors
Accuracy in Q factor measurements made for low loss mechanical systems is limited by noise in long-term
amplitude ring down curves. In particular seismic noise can couple strongly to a pendulum. By correlating
seismic data with a ring down curve it should be possible to remove the variation in amplitude due to
seismic excitation. Here we present data that suggests that the variation in pendulum amplitude is highly
correlated to seismic noise. Removal of the seismic signal allows a more accurate determination of the
pendulums Q factor. In addition the technique could allow the Q factor to be determined without large
amplitude mechanical excitation.
POSTER
PAI
A. Pai
IUCAA
Computational Cost for Detecting Compact Binaries using a Network of Laser Interferometric Detectors
We extend the data analysis strategy developed for the network of detectors for Newtonian chirp waveform
to the post-Newtonian (PN) case. As the PN waveform depends on both the masses of the inspiraling
binary, dimension of the parameter space to be scanned increases by one from that for the Newtonian case.
We employ Tagoshi-Tanaka coordinates to obtain the number of templates and estimate the online
computational costs. For the lower mass limit of 1 M•
the number of PN templates for LIGO-I noise
O
with 3% mismatch increases by a factor of 6. If the lower mass is reduced to 0.5 M •
O , the number of PN
templates is 11 times more than that for the Newtonian case. We study realistic cases of Networks
comprising of LIGO and VIRGO detectors. We present the computational speed requirements, and the
source-direction resolutions for various network configurations.
POSTER
PARFENOV
V.Parfenov, N.Kravtsov, V.Firsov, Vl.Parfenov, S.Kruzhalov, S.Rustamov
Research Center S.I.Vavilov State Optical Institute
High-Stable Single-Frequency Nd:YAG Lasers
Frequency-stabilized high-power lasers are required for interferometric gravitational wave detectors and
metrology systems of stellar interferometers. High absolute stability of laser frequency is very important in
both cases. We report on the design and performance of high-stable single-frequency Nd:YAG lasers
which could be used in gravitational wave detectors and metrology systems of long-baseline
interferometers. One of these lasers is frequency-doubled Nd:YAG oscillator locked to Fabry-Perot cavity.
Its output is of 60 mW, spectral linewidth is of 1 MHz and a frequency drift is lower than 0.5 MHz per
secund. Another laser is 80 mW, 1064 nm, diode-pumped Nd:YAG one having monolithic cavity design,
that is insensitive to acoustic noise. This laser linewidth is of about 10 KHz, and a thermal frequency drift
of approximately 1 MHz per minute. Further reduction of the lasers frequency noise can be achieved by
means of stabilization systems using atomic resonances as references. Using the generation wavelength of
532 nm, we have recorded the hyperfine spectrum of absorption lines of iodine. The experimental results
on locking the frequency of Nd:YAG laser to resolved spectral components will be presented in the paper.
Amaldi 4
Abstracts
Page 34
POSTER
PARFENOV
V. A. Parfenov
Research Centre S.I.Vavilov State Optical Institute
V. A. Parfenov
State Technical University
Compact Universal Faraday Isolator Based On Nd:Fe:B Permanent Magnets
In many modern photonic devices for optical communications, interferometry and in high-power laser
systems for achievement of stable operation and good performance it is often required to isolate the laser by
attenuating reflected and backscattering light by several orders of magnitude. In many cases, this can only
be achieved with optical isolator. The fundamental arrangement of optical isolator consists of linear
polarizer, an optical element that exhibit nonreciprocal behaviour in a longitudinal magnetic field, and a
second polarizer which is rotated by 45 degree with respect to the first one. One such class of mentioned
optical element is based on the Faraday effect, in which the rotation of plane-polarized light is dependent
on only the applied magnetic field and is not dependent on the direction of light propagation. In the paper
we report on the concept and performance of compact, high-effective optical isolator in which Nd:Fe:B
permanent magnets based Faraday rotator is used. The architecture of the Faraday rotator is based on novel
3-pass geometry that makes it a compact and cost-effective. Faraday rotator of the isolator rotate the plan of
polarization of light by 45 degree in a wide range of wavelength and can be used for work with lasers
generating in the visible and near infrared. The degree of optical isolation of the device of at least 30 dB is
achieved when operating with laser beams of up to 2 mm, and up to 25 dB when the aperture of the
magneto-optic element is completely filled.
ISOLATION and SUSPENSION - Wednesday
PASSUELLO
D. Passuello
INFN Sez di Pisa
Controlling the Virgo Mirrors with the SuperAttenuator
Abstract not available.
DATA ANALYSIS - Tuesday
PINTO
R.P. Croce (WavesGroup, University of Salerno, IT)
Th. Demma, V. Pierro, I.M. Pinto (Waves Group, University of Sannio, IT)
Cardinal Interpolation of the Post-1-Pn Match Via Tanaka-Tagoshi Coordinates
The spin-free binary-inspiral parameter-space introduced by Tanaka and Tagoshi to construct a uniformlyspaced lattice of templates at (and possibly beyond) 2.5PN order is shown to work for all first generation
interferometric gravitational wave antennas, under a given minimal match constraint. The Tanaka Tagoshi
waveform parametrization allows to extend the minimum-redundant cardinal interpolation techniques of
the match developed by the Authors in to the highest available order PN templates, yielding a reduction in
the total number of post-1PN templates needed for a minimal match   0.97 by a factor4, as in the 1PN
case.
Amaldi 4
Abstracts
Page 35
OPERATING DETECTORS - Tuesday
PRODI
G.A.Prodi (International Gravitational Event Collabotation)
University of Trento and INFN
Search Of Gravitational Wave Bursts By The Network Of Resonant Detectors.
The International Gravitational Event Collaboration is operating as a worldwide observatory for
gravitational wave bursts. During 1997-2000, five cryogenic resonant detectors have been in operation.
This configuration of the observatory ensures a good coverage of the Galactic mass during time and is able
to identify single candidates with very low false alarm rates when at least three detectors are operating in
coincidence. The main results of the 1997-2000 observations of the IGEC network will be presented. The
prospects for future improvements and for new capabilities of the observatory will be outlined.
ISOLATION and SUSPENSION - Wednesday
PUNTURO
P.Amico, L.Bosi, L.Carbone, L.Gammaitoni, M.Punturo, F.Travasso, H.Vocca
Istituto Nazionale di Fisica Nucleare
Thermal Noise Limit To The Virgo Sensitivity: Monolithic Approach
Thermal noise is the main limit to the Virgo sensitivity in the 5-500Hz range. A monolithic suspension
design and more performant material are investigated to reduce the pendulum thermal noise and the mirror
thermal noise. Experimental measurements on the performance of such as suspension are presented.
CONFIGURATIONS - Wednesday
REITZE
D. H. Reitze, T. Delker, G. Mueller, and D. Tanner
University of Florida
Demonstration And Characterisation Of A Tabletop Cavity-Enhanced, Dual Recycled Interferometer
The next generation of large-scale gravitational wave detectors will incorporate signal recycling as a way of
enhancing their sensitivity and reach. To understand the additional complexities incurred by this
interferometer topology, compact table-top prototype experiments must be carried out to develop length
sensing and control schemes, test lock acquisition methods, and demonstrate tunable operation. We present
the results on the design and operation of one possible advanced interferometer configuration, a cavityenhanced, dual recycled interferometer. We will discuss the general considerations for designing a length
sensing system and describe the experimental realization of a dual recycled interferometer with Fabry-Perot
arm cavities. Both broadband and detuned operation has been obtained, with a displacement sensitivity
enhancement of approximately 7 times over a power-recycled configuration. We will also discuss
scalability to km class interferometers.
POSTER
REPIN
S. Repin and A. Zakharov
Space Research Institute, RAS
Observational Manifestation of General Relativity in Accretion Disk Spectra
Recent observations of Seyfert galaxies in X-ray band (ASCA, RXTE, Chandra) seem to indicate that
broad iron K line takes its origin in the innermost area of the accretion disks. In the region (1-5)rg, where
the line is assumed to arise, the effects of General Relativity must be taken into account.
A spectrum of a solitary emission line, appeared in Kerrian accretion disk, has been simulated, depending
on the radial coordinate r and the angular momentum a=J/M of a black hole, under the assumption of
equatorial circular motion of the matter. It is shown that the characteristic two-peak line profile arises at a
Amaldi 4
Abstracts
Page 36
large distance r ~ (3-10)rg or large inclination angle. The inner regions emit the line with one maximum
and extremely wide red wing. The time evolution of the line profile includes the information about the
gravitational emission.
POSTER
RICCI
S. Braccini(4) C. Casciano(4), F. Cordero(3), F.Frasconi(4), G. P. Gregori (5), E.Majorana(1), G.
Paparo(3), R.Passaquieti(4), P. Puppo(1), P. Rapagnani(1;2) and F. Ricci(1;2)
(1) INFN, Sezione di Roma 1, Roma, Italy
(2) Dip. di Fisica, Univ. di Roma "La Sapienza", Roma, Italy
(3) Ist. di Acustica "O.M. Corbino",C.N.R., Roma, Italy
(4) INFN, Sezione di Pisa, San Piero a Grado (PI), Italy
(5) Ist. di Fisica dell'Atmosfera, C.N.R., Roma, Italy
Monitor of the Acoustic Emission on the Maraging Spring-blades of the VIRGO Superattenuator.
One of the most important components of the VIRGO suspension system is the cantilever triangular blade.
The material used for its construction is Maraging steel, a low carbon content alloy with high hardness and
low creep under stress. Since the acoustic emission associated with dislocations motion can be a potential
source of non-stationary noise for gravitational wave experiments, we investigated on the possibility to
reduce this process. The Acoustic Emission technique has been used to monitor the ultrasonic pulses while
the triangular structure was loaded up to 50 kg. According to these measurements we have collected several
set of events getting evidence of a material memory e ect (Kaiser e ect) associated to the dislocation motion
in the Maraging steel. This result has been obtained by applying a standard fractal analsysis procedure (box
counting method) to the timing series of acoustic emission bursts. We conclude that a reduction of the
ultrasonic processes on the blade was obtained by applying few stress cycles to the metallic structure
improving, at the same time, its stability on the microscopic scale.
RESONANT MASS DETECTORS - Friday
RONGA
P. Astone, M. Bassan, P. Bonifazi, P. Carelli, E. Coccia, S.DíAntonio, V. Fafone, G.Federici, A. Marini, G.
Mazzitelli, Y. Minenkov, I. Modena, G. Modestino, A.Moleti, G. V. Pallottino, V. Pampaloni, G. Pizzella,
L.Quintieri, F. Ronga ,R.Terenzi ,M.Visco, L. Votano
INFN Laboratori Nazionali di Frascati
Energetic Cosmic Rays Observed By The Resonant Gravitational Wave Detector NAUTILUS
Cosmic ray showers interacting with the resonant mass gravitational wave antenna NAUTILUS have been
detected. The experimental results show large signals at a rate much greater than expected. The largest
signal corresponds to an energy release in NAUTILUS of 87 TeV. To explain data, among several
possibilities, one can invoke unexpected behaviour of superconducting aluminium as particle detector,
producing enhanced signals, the excitation of non-elastic modes with large energy release or anomalies in
cosmic rays.
SOURCES - Monday
SADOYAN
A. Abel Sadoyan and G. Alodjanc
Yerevan State University
Gravitational Waves From A Possible Model Of X-Ray Bursts And Soft Gamma Repeaters
We present a possible model for a X-ray burster that in a special circumstances converts to Soft Gamma
Ray repeater. We consider a binary accreting system with superdense component in the center that is near
to the Eddington limit. In special cases accreting matter forms a layer with a high opacity near the surface
of superdense body. The thermal energy of nucleus reaches the highest possible value, when luminosity
becomes much bigger then Eddington Limit. Accretion on neutron star surface stops and a thin layer of
accumulated matter burst back. We consider narrow beaming angle near the poles and calculate the
Amaldi 4
Abstracts
Page 37
amplitude and energy emitted in GW during the outburst. We present our results of numerical simulations
and discuss the question of SGRs as possible candidates for detectable GW sources.
POSTER
SADOYAN
A.A. Sadoyan
Yerevan State University
Computer Simulation of GW Emission during SGR Activity
We report the computer simulation of Gravitation Wave emission during Soft Gamma Repeater activity. A
highly flexible accretion in binary system is considered. Original method for calculations is used to solve
the set of equations describing the evolution for accreting configurations in the framework of Einstein
theory of gravitation. This method allows tracing relativistic shock waves (in our case the external shocks)
that are the sources of gamma emission. We present the time evolution of GW emission, variability, and
dependence of amplitude from parameters of accreting binary system.
POSTER
SCHEDIWY
S. Schediwy1, J. Winterflood2, D. Blair2 and M. Zadnik1
1
Curtin University
2
The University of Western Australia
Thermal Actuation for Control of Very Low Frequency Vertical Pre-isolation Stage.
The vertical pre-isolator used by the UWA group is based on a Lacoste Isolator. This type of isolation
requires that the spring element is subject to a control system due to the varying temperature coefficient of
Young’s Modulus. We report a method where we are able to control the vertical displacement of the preisolator by applying a small current to the spring element. This allows the natural range of 35 millimetres to
be controlled to better than 2 millimetres.
DATA ANALYSIS - Tuesday
SEARLE / SCOTT
A.C. Searle and S.M. Scott
Australian National University
A Numerical Model of a Global Array of Gravitational Wave Detectors
We detail an extensible numerical model of a global array of interferometric gravitational wave detectors.
The system computes signal strength for each detector and combines these data using recently proposed
network analysis techniques and Monte-Carlo methods to produce a relative detection rate for the network
as a whole. Computation over multiple detector locations and orientations are used to investigate optimal
network configurations for signals from a standard candle short-duration source of gravitational waves.
POSTER
SENGUPTA
A.S. Sengupta, S. V. Dhurandhar, A. Lazzarini and T. Prince
Inter-University Centre for Astronomy and Astrophysics
Extended Hierarchical Search (EHS) Algorithm For Detection Of Gravitational Waves From Compact
Coalescing Binaries
Gravitational waves from inspiralling compact binaries are considered to be the most promising sources for
laser interferometric gravitational wave detectors. Since the waveform can be determined fairly accurately,
matched filtering techniques can be employed to optimally extract the signal from the detector noise. Since
the signal depends on several parameters such as masses, time of arrival, initial phase etc., the search needs
to be carried out over a multidimensional parameter space. Employing a grid of templates spanning the full
Amaldi 4
Abstracts
Page 38
parameter space is computationally expensive.
minimize the computational cost.
Thus one must devise efficient search strategies to
To this end, the hierarchical search algorithm (Mohanty and Dhurandhar, 1996), led to a significant
reduction in computational cost, wherein, two template grids were used instead of the conventional one
grid. The templates in a "coarser" grid, employing a lower threshold, were used as a trigger phase, which
was then followed up by a fine grid around the points that exhibited crossings. The improvement in the
cost as compared to a search performed totally by a fine grid search for the LIGO I noise curve was shown
to be between 20 and 30.
We show that a further reduction in computational cost is possible if we extend the hierarchy paradigm to
an extra parameter, namely, the time of arrival of the signal in the band of the detector. In the first stage the
chirp waveform is cut-off at a low frequency so that the sampling rate can be reduced leading to reduction
in computational cost. But the cut-off is chosen sufficiently high in order that there is enough signal power,
so that the hierarchy in masses is not compromised. This is possible since the waveform has most of its
power at low frequencies. Results are obtained for spin less 2PN templates. We find that the gain in
computational cost over a brute force search is well over 100.
CONFIGURATIONS - Wednesday
SHADDOCK
D. A. Shaddock, M. B. Gray, C. Mow-Lowry and D. E. McClelland
Australian National University
Experimental Demonstration Of A Continuously Tunable RSE Michelson Interferometer
We present experimental results of a bench-top power recycled Michelson interferometer with resonant
sideband extraction. The interferometer allowed 4 degrees of freedom to be locked to a fixed point whilst a
fifth degree of freedom, the signal cavity, was detuned to an arbitrary position. The control system allowed
the signal cavity to be detuned without the interferometer losing lock. We present details of the frontal
modulation control system as well as the measured signal response of the device for several different signal
cavity detunings.
OPTICAL SUBSYSTEMS - Thursday
SHADDOCK
D. A. Shaddock
Australian National University
Double Pass Tilt Locking of a Pre-Mode-Cleaner Cavity
Abstract not available.
OVERVIEWS - Monday
SHOEMAKER
D. Shoemaker
Massachusetts Institute of Technology
Status of Interferometers and Data Analysis
The talk will briefly describe the present ground-based interferometers world-wide, and the plans for
analyzing the data from those interferometers. An overview of the next-generation thinking for
interferometers will also be given -- where we hope to be toward the end of the decade.
Amaldi 4
Abstracts
Page 39
LASERS and OPTICS - Thursday
SHOEMAKER
R. Lawrence, D. Shoemaker M. Zucker
Massachusetts Institute of Technology
Adaptive Thermal Compensation of Test Masses
As the first generation of laser interferometric gravitational wave detectors near completion, research and
development has begun on increasing the instrument's sensitivity while utilizing the existing infrastructure.
In the Laser Interferometer Gravitational Wave Observatory (LIGO), incremental upgrades are being
planned to occur within the next five years, improving strain sensitivity though active seismic isolation
systems, lower loss optical materials, and higher input laser power. Even with the highest quality optics
available today, however, finite absorption of laser power within transmissive optics, coupled with the
tremendous amount of optical power circulating in various parts of the interferometer, result in critical
wavefront deformations which will cripple the performance of the instrument. Discussed is a method of
active wavefront correction via direct thermal actuation on optical elements of the interferometer. A simple
Nichrome heating element suspended at a short distance from the face of an affected optic will, through
radiative heating, remove the gross axisymmetric part of the original thermal distortion. A scanning heating
laser will then be used to remove any remaining non-axisymmetric wavefront distortion, generated by
inhomogeneities in the substrate's absorption, thermal conductivity, etc. A proof-of-principle experiment
has been constructed at MIT, selected data from which will be presented.
OPERATING DETECTORS - Tuesday
SIGG
D. Sigg
The LIGO collaboration
Commissioning of the LIGO detectors
The goal of the Laser Interferometer Gravitational-wave Observatory (LIGO) Project is to detect and study
gravitational waves from astrophysical sources. Currently, three interferometers with arm lengths of
several kilometers and a design strain sensitivity of order 2 10-23 /Hz are being commissioned at two
independent sites in Hanford (WA) and Livingston (LA). This talk describes the current work towards
achieving LIGO's final sensitivity.
ISOLATION and SUSPENSION - Wednesday
SLAGMOLEN
B. Slagmolen
Australian National University
Techniques for Thermal Noise Measurements: A Progress Report
The ANU Thermal noise project is concentrated around a one dimensional BeCu flexure pendulum. The
flexure pendulum is designed to have a resonant frequency of 20Hz, and a Q-factor of 1000. Attached to
this flexure pendulum is the end mirror of a short linear high finesse cavity. Currently ring down
measurements of the flexure pendulum resonant are done to record the transfer function of the flexure
pendulum.
POSTER
STARK
E. M. Stark and A. Lun
Monash University
Abstract not available.
Amaldi 4
Abstracts
Page 40
POSTER
STROHMAYER
T. Strohmayer
NASA's Goddard Space Flight Center
Gravity Waves from Rotating Neutron Stars and Evaluation of Fast Chirp Transform Techniques
X-ray observations suggest that neutron stars in low mass X-ray binaries (LMXB) are rotating with
frequencies from 300 - 600 Hz. If accretion induced spin up is in equilibrium with gravitational radiation
losses, these objects could be interesting sources of gravity waves. I present a summary of current
measurements of neutron star spin in LMXBs and will also present a study of fast chirp transform
techniques as described by Jenet and Prince (2000) in the context of chirping signals observed during Xray bursts.
POSTER
SUTTON
P. J. Sutton and L. S. Finn
Pennsylvania State University
Bounding the Mass of the Graviton Using Binary Pulsars
A new method for bounding the mass of the graviton is presented, based on the agreement between the
observed orbital decay of binary pulsar PSR 1913+16 and the predictions of general relativity. This bound
is the first to be based on dynamic rather than static-field relativity. Furthermore, the limit on the graviton
mass is comparable to that obtained from solar system measurements, and will improve with further
observations.
ISOLATION and SUSPENSION - Wednesday
TAKAHASHI
R. Takahashi, K. Arai and the TAMA collaboration
National Astronomical Observatory
Improvement of Vibration Isolation System for TAMA300
We will report status of vibration isolation system for TAMA300. Topics are improved mirror suspensions
and newly installed active isolation system which realize stable operation of the interferometer. RMS
amplitude of seismic vibration at 1-10Hz was improved from 6-11mgal to less than 2mgal. A full-time
observation by TAMA300 with the new isolators is planned.
ISOLATION and SUSPENSION - Wednesday
TAKAMORI
A. Takamori, M. Ando, A. Bertolini, G. Cella, R. DeSalvo, M.Fukushima, S. Kawamura, Sz. Marka, K.
Numata, V. Sannibale, K. Somiya, R. Takahashi, H. Tariq, K. Tsubono, J. Ugas, N. Viboud, H. Yamamoto,
T. Yoda, C. Wang
California Institute of Technology
Seismic Attenuation System for TAMA300 (TAMA SAS): operation in a prototype interferometer
We have developed the Seismic Attenuation System (SAS) technology for the next generation of
interferometric gravitational wave detectors. The main goals of SAS are to improve detector sensitivity at
low frequency, below 100 Hz, and enable robust and stable GW observation with highly sensitive
detectors. To achieve large attenuation factor at low frequencies (10 Hz -100 Hz) , the SAS uses a chain of
three-dimensional passive mechanical isolators with rigid body modes in the very low frequency region (20
mHz - 500 mHz). Inertial damping with digital control techniques and highly sensitive sensors are also
used to reduce residual displacement of the system. TAMA-SAS, developed under the collaboration
between LIGO and TAMA, consists of the SAS and a new TAMA suspension composed of a double
pendulum and a reaction mass. Two units of the TAMA-SAS have been installed and tested at the 3m
Amaldi 4
Abstracts
Page 41
prototype interferometer in the University of Tokyo since March 2001. The recent results of the experiment
would be reported and discussed.
POSTER
TERENZI
R. Terenzi
CNR: Consiglio Nazionale delle Ricerche
IGEC database System: a building block for network gavitational events data analysis
The IGEC database system has now the provision for real-time data graphics presentation to show the
status data of the network of the five gravitational resonant detectors of the IGEC collaboration. These data
are going to be publicly available by querying the database using standard web-browsers. This has been
achieved by interfacing the relational database system with standard mathematical and graphics software
using a network distributed system. We think that such a system architecture based on distributed systems
and on the interface of relational data base with mathematical software and WEB software, can be an
effective building block for a gravitational events data analysis system.
OVERVIEWS - Monday
THORNE
K. S. Thorne
Caltech
Quantum Nondemolition Interferometers
Advanced LIGO interferometers (``LIGO-2''; 2008- ) will operate near and possibly below the standard
quantum limit (SQL), and a subsequent generation of interferometers is likely to operate a factor 4 or more
below the SQL. An overview will be given of the fundamental quantum nondemolition (QND) principles
that make this possible. These principles will be illustrated by specific designs for QND interferometers
that have been developed in recent years. Some experimental challenges involved in implementing these
designs will be described, and some vague ideas for improved QND designs will be sketched.
SPACECRAFT METHODS - Wednesday
THORNE
K. S. Thorne
Caltech
LISA Science
LISA (the Laser Interferometer Space Antenna) is expected to be launched, as a joint ESA/NASA Mission,
in 2011. An overview will be given of the various gravitational-wave sources that may be detected and
studied by LISA, their wave strengths, event rates, and waveforms, the science we hope to extract from the
observed waveforms, and the challenges that must be surmounted between now and 2011 if this science is
to be realized. The challenges are primarily of two types: the computation of waveforms for use in data
analysis, and the scoping out and development of data analysis algorithms.
POSTER
TINTO
M. Tinto
Jet Propulsion Laboratory, California Institute of Technology
The CASSINI Ka-Band Gravitational Wave Experiments
Experiments aimed at the detection in space of gravitational waves, by using the coherent microwave link
between a ground radio telescope and an interplanetary spacecraft, have been performed over the past two
decades. Unfortunately none of those attempts led to an unambiguous detection. However, starting
November 29, 2001 the CASSINI spacecraft will be continuously tracked for a period of forty days at KaBand, and at an anticipated sensitivity level well below the levels measured with previous missions.
Amaldi 4
Abstracts
Page 42
This talk provides an overview of the CASSINI onboard Ka-Band configuration, as well as the Ka-Band
implementation at one of the 34 meters Beam Wave Guide antennae of the NASA Deep Space Network
(DSN). The stringent frequency stability requirements on the coherent microwave link between the DSN
station and the spacecraft have implied the implementation of superior ground station stability, and
sophisticated calibration of the frequency fluctuations due to the atmosphere. Specific capabilities added to
one of the DSN 34-m beam wave-guide include stable frequency and timing, precision Ka-Band pointing,
and extremely low noise Ka-band receivers. A summary of the anticipated CASSINI sensitivities to
specific gravitational wave forms will then be presented as part of our conclusions.
RESONANT MASS DETECTORS - Friday
TOBAR
M. E. Tobar, C. R. Locke and E. Ivanov
The University of Western Australia
Prospects of Measuring and Surpassing the Standard Quantum Limit using Parametric Transducers
Recent results of the development of a sapphire monocrystal parametric transducer will be presented. The
transducer consists of a sapphire bar with an acoustic frequency of 53 kHz. The transductance scheme is
implemented by exciting high-Q Whispering Gallery Modes internal to the sapphire bar. Transductance is
mainly achieved through the strain dependence of dielectric constant of sapphire. High electrical and
acoustical Q-values are possible as the bonding of a transducer is not required and the method of coupling
is via non-contacting microwave electric and magnetic probes. New results show that the displacement
sensitivity of Transverse Electric and Transverse Magnetic polarized modes is out of phase by 180 degrees
with respect to the acoustic frequency of the sapphire bar. We will show that this allows the new concept of
Dual-Mode transducer readout allowing a new type of back action evasion (BAE) read-out. Unlike other
BAE or QND transducers, this read-out only requires one pump source, with the two modes separated in
frequency by twice the acoustic frequency. The measured noise properties of the prototype transducer will
be presented and the prospects of reaching and surpassing the standard quantum limit will be discussed.
POSTER
TOMARU
T. Tomaru, T. Suzuki, T. Uchiyama, S. Miyoki, M. Ohashi, K. Kuroda, A. Yamamoto, T. Shintomi, B.
Bochner, P. Saha, Y. Hefetz
High Energy Accelerator Research Organization, Cryogenics Science Center
Thermal Lensing In Cryogenice Sapphire Substrates
Thermal lensing is most serious problem when we use sapphire mirrors. Since thermal conductivity of
sapphire increases and temperature coefficient of refractive index decreases at cryogenic temperature,
thermal lensing vanish at cryogenic temperature even if sapphire has large optical absorption.
POSTER
TSIPENYUK
D.Yu.Tsipenyuk and V.A. Andree
General Physics Institute of the Russian Academy of Sciences
Structure of the Extended Space
We put forward an idea that physical phenomena have to be treated in 5-dimensional space where the 5-th
coordinate is the interval S [1]. Thus, we considered the (1+4) extended space G(t,x,y,z,S). In addition to
Lorentz transformations which are in 4-dimentional Minkowski space, in the proposed 5-dimentional
extended space G two other transformations exists. This transformations can convert massive particles into
massless and vice versa. Energy-momentum-mass space conjugates to the time-coordinate-interval
(t,x,y,z,s) space, so the mass is corresponds to the interval S. So well known energy-momentum 4-vector
P(1+3)=(E/c;p(x);p(y);p(z)) in the Minkowski M(T,X,Y,Z) space is transformed to the 5-vector
P(1+4)=(E/c;p(x);p(y);p(z);mc)=(E/c;P;mc) in the extended space G and becomes isotropic for 5-vectors of
the massive (mc;0;mc) as well as for massless (hw/c;hw/c;0) particles. 1.Tsipenyuk D.Yu.,Andreev
Amaldi 4
Abstracts
Page 43
V.A.Kratkie soobstcheniya po fizike(in Russian), N6,pp.23-34,(2000). (Bulletin of the Lebedev Physics
Institute (Russian Academy of Sciences), Alerton Press, Inc.,N.Y.)
POSTER
TSIPENYUK
D.Yu.Tsipenyuk
General Physics Institute Moscow
Gravitation Effects in the Model of the Extended Space: Deflection of Starlight, Red Shift, Shapiro Timedelay
We developed an idea that physical phenomena have to be treated in 5-dimensional space where the fifth
coordinate is the interval S. Thus, it was considered the (1+4) Extended Space G(T,X,S). It was considered
general principles of constructing of interaction between different objects in the Extended Space.
According to them both vector electromagnetic field and the gravitational field are generated by the same
5-vector potential. In the empty Minkowski (1+3) space M(T,X) (S=0) these fields are independent one
from another. But if the space is filled with some material medium so that parameter S not equal to 0, these
two fields form unified field and their components can interact with each other. On the base of the model of
gravitation interaction in the Extended Space we can obtain the same predictions as the theory of relativity:
the deflection of starlight, gravitation red shift, Shapiro time-delay, in addition we can predict something
new: second order correction in the red shift and direct transformation of the electromagnetic field to the
gravitation field during deceleration of the charged particles.
POSTER
VALLURI
S. R. Valluri, F. A. Chishtie, R. G. Biggs, M. Davison, S. V. Dhurandhar, B. S. Sathyaprakash
University of Western Ontario
A Study of the Gravitational Wave Signal From a Pulsar
We present a Fourier Transform (FT) of the gravitational wave (GW) signal from pulsars. Due to the
rotation and orbital motion of the Earth, a monochromatic GW signal becomes frequency and amplitude
modulated. The bandwidth about the signal frequency of the wave becomes an important aspect due to the
Doppler modulation. We have obtained an analytic closed form of the FT considering both the rotational
and orbital motion of the Earth. We make a detailed numerical analysis of the FT and study its dependence
on the bandwidth and the angular momentum l. This study will be a precursor to Principal Component
Analysis which could facilitate the choice of search templates in a multidimensional parameter space
dependence of a pulsar source.
SOURCES - Monday
VAN PUTTEN
M. H.P.M. van Putten (MIT) and A. Levinson (Tel Aviv)
Calorimetry Of Gamma-Ray Bursts: Echos In Gravitational Waves
Black holes surrounded by a disk or torus may drive the enigmatic cosmological gamma-ray bursts
(GRBs). Equivalence in poloidal topology to pulsar magnetospheres shows a high incidence of the black
hole-luminosity LH into the surrounding magnetized matter. We argue that this emission is re-radiated into
gravitational waves at LGW  LH/2 in frequencies of order 1kHz, winds and, potentially, MeV neutrinos. The
total energy budget and the input to the GRB from baryon poor jets are expected to be standard in this
scenario, consistent with recent analysis of afterglow data. Collimation of these outflows by baryon rich
disk or torus winds may account for the observed spread in opening angles up to about 35 o. This model
may be tested by future LIGO/VIRGO observations.
Amaldi 4
Abstracts
Page 44
DATA ANALYSIS - Tuesday
VECCHIO
A. Vecchio
The University of Birmingham
LISA and Gravitational Wave Stochastic Background
A great variety of gravitational wave stochastic backgrounds populate the sensitivity window of LISA:
signals produced by galactic and extra-galactic populations of close binary systems, and relic gravitons
generated in the early-Universe. We review our present astrophysical understanding of the main sources,
address the prospects of detection with LISA, and discuss whether space interferometers could provide
information on the background anisotropy.
POSTER
VEDOVATO
G. Vedovato1, L. Baggio3, M. Cerdonio2, A. Ceseracciu1, A. Ortolan1, G.A. Prodi3, S.Vitale3, L. Taffarello2,
P. Zendri2
1) I.N.F.N., National Labs of Legnaro
2) Univ. and I.N.F.N. of Padova
3) Univ. of Trento, I.N.F.N. of Padova
A Frame Based Data Acquisition and Analysis Systems for GW Experiment AURIGA
AURIGA is a resonant gravitational wave (gw) detector located at the INFN-National Laboratories of
Legnaro in Italy, able to detect short bursts. AURIGA is currently member of the IGEC collaboration
among resonant cryogenic bars, and will be part of an intercontinental network of bar and interferometer
gw detectors. To satisfy these new requirements our group has decided to redesign both the Data
Acquisition and the Analysis Systems, adopting the FRAME format (developed by VIRGO/LIGO) for the
Input/Output and data exchange. The PC Linux, the open source tools and libraries and the C++
programming language have been the natural choice for the development platform. We have developed two
libraries: i) the Process Control Library (PCL) aimed to manage communications and controls of the user
processes, and ii) the AURIGA Algorithm Library (AAL) which gathers the specific algorithms of the
AURIGA analysis (Adaptive Filters, Template Matching, Trigger Search, Data Quality).
POSTER
VELLOSO
W. F. Velloso Jr., J. L. Melo and O. D. Aguiar
INPE - Brazilian National Institute for Space Research
Vibration Isolation Support System for SCHENBERG Detector
We designed a mechanical isolation system for a spherical resonant gravitational wave detector we are
building in Brazil. We have used the Finite Element Method to perform the dynamical analysis. The system
is a multiple stage passive pendulum formed by cylinders joined by C springs and rods. Our results showed
that the designed system could allow a very good damping factor in the bandwidth, from 3.0 kHz to 3.4
kHz, where the SCHENBERG detector will be sensitive.
POSTER
VINANTE
A. Vinante, R. Mezzena, G. A. Prodi, S. Vitale:
Universit‡ di Trento and INFN
P. Falferi, M. Bonaldi:
Centro di Fisica degli Stati Aggregati and INFN, Gruppo collegato di Trento, Sezione di Padova
M. Cerdonio: Universit‡ di Padova and INFN
Amaldi 4
Abstracts
Page 45
A 200 Hbar Two-Stage Dc SQUID For Resonant Detectors
Starting from Quantum Design chips a two stage dc SQUID system was developed in order to be used as
low noise amplifier on the resonant gravitational wave detector AURIGA. The system was coupled to a
high Q electrical resonator, operating in the kHz frequency range, that was employed to simulate the real
detector. The resonator was successfully stabilized by means of a capacitive feedback loop. SQUID
wideband noise and resonator narrowband noise were measured in the temperature range 1.5 K - 4.2 K. The
best noise temperature measured at 1.5 K was better than 15 uK, corresponding to 200 hbar.
RESONANT MASS DETECTORS - Friday
VISCO
P.Astone, M.Bassan, P.Bonifazi, P.Carelli, M.G.Castellano, G.Cavallari, E.Coccia, C.Cosmelli,
S.D'Antonio, V.Fafone, Y.Minenkov, I.Modena, G.Modestino, A.Moleti, G.V.Pallottino, G.Pizzella,
L.Quintieri, F. Ronga, R.Terenzi, G.Torrioli, M.Visco
CNR - Istituto di Fisica dello Spazio Interplanetario
The New Run Of The Explorer Resonant Gravitational Wave Detector
The gravitational wave resonant detector EXPLORER, located at CERN, operates at the temperature of 2.5
K, taking data since 1990 with good performance. Data from extended periods have been used for
coincidence studies with the other detectors operating worldwide. Recently the antenna has been improved
adopting a new read-out. A new capacitive resonant transducer and a new dcSQUID led to a remarkable
improvement of the performance: a detector noise temperature of about 2mK and a bandwidth of almost 10
Hz have been obtained. The larger bandwidth is particularly interesting as it is an order of magnitude larger
than all other operating resonant detectors.
ISOLATION and SUSPENSION - Wednesday
VOCCA
P.Amico, L.Bosi, L.Carbone, L.Gammaitoni, M.Punturo, F.Travasso and H.Vocca
INFN
Fused Silica Suspension For The Virgo Optics: Status And Perspectives
Fused silica fibers will be the alternative to the steel wires to realize a low thermal noise suspension for the
Virgo optics. A new production facility is presented. Experimental tests on the mechanical quality factor
and stress strength are shown. Experimental measurements on the strength of potassium silicate bonding are
reported.
POSTER
WALUSCHKA
E. Waluschka
Goddard Space Flight Center, NASA
LISA telescope sensitivity analysis
The results of a LISA telescope sensitivity analysis will be presented. The emphasis will be on the outgoing
beam of the Dall-Kirkham telescope and its far field phase patterns. The computed sensitivity analysis
will include motions of the secondary with respect to the primary, changes in shape of the primary and
secondary, effect of aberrations of the input laser beam and the effect the telescope thin film coatings on
polarization. An end-to-end optical model will also be discussed.
POSTER
WEBER
William Weber (1,2,3), Antonella Cavalleri (4), Rita Dolesi (1,2),
Giorgio Fontana (5), Mauro Hueller (1,2), and Stefano Vitale (1,2,3)
1.
2.
3.
Universita' di Trento, Dipartimento di Fisica
Istituto Nazionale di Fisica Nucleare (INFN)
Consorzio Criospazio Ricerche (CCR)
Amaldi 4
Abstracts
Page 46
4.
5.
Centro Fisica dello Stato Aggregato (CEFSA)
Universita' di Trento, Dipartimento di Ingegneria
Progress in the Development of Free Fall Sensors for LISA
The extreme level of isolation from stray forces required for LISA makes the development of ``Drag Free
Control'' technologies essential to the success of the mission. We report here on our progress in the
development of a capacitive, six degree of freedom, position sensor designed to meet the required low
levels of position readout noise (1 nm / Hz 1/2) and stray force noise (3.e-15 N / Hz1/2) across the LISA
bandwidth of .1 mHz to .1 Hz. This poster presents the design and construction of our sensor and its
electronic readout, expected performance and sources of noise, and, additionally, laboratory
measurements of the prototype sensor's noise level and sensitivity.
CONFIGURATIONS - Wednesday
WEINSTEIN
A. Weinstein
California Institute of Technology (Caltech)
Advanced LIGO optical configuration and controls
The motivations for, and straw-man design of, an Advanced LIGO optical configuration (dual-recycled
Michelson with Fabry-Perot arms) will be described, with special attention to the control scheme proposed
in August 2000. The status of simulations based on the Twiddle, E2E, and FFT packages will be discussed.
Plans for suspended-optic prototypes of the optical configuration, including a full engineering prototype at
Caltech's 40 meter interferometer laboratory, will be described.
SOURCES - Monday
WHELAN
J. T. Whelan, C. Beetle, W. Landry, R. Price
UT Brownsville
Radiation-Balanced Simulations for Binary Inspiral
The late stage of the inspiral of two black holes may have important non-Newtonian effects that are
unrelated to radiation reaction. To understand these effects we approximate a slowly inspiralling binary by
a stationary solution to Einstein's equations in which the holes orbit eternally. Radiation reaction is
nullified by specifying a boundary condition at infinity containing equal amounts of ingoing and outgoing
radiation. The computational problem is then converted from an evolution problem with initial data to a
boundary value problem. In addition to providing an approximate inspiral waveform via extraction of the
outgoing modes, our approximation can give alternative initial data for numerical relativity evolution.
Results will be reported on simplified models and on progress in building 3D numerical solutions.
POSTER
WHELAN
J. T. Whelan, M. C. Diaz, Ik Siong Heng, J. D. Romano, A. Vecchio,
The University of Texas at Brownsville
Progress on Stochastic Background Search Codes for LIGO
The routines to perform the analysis of data from the Laser Interferometer Gravitational-wave Observatory
(LIGO) are part of the LIGO/LSC (LIGO Scientific Collaboration) numerical Algorithm Library (LAL). I
will describe the standard technique to search for a stochastic background of gravitational waves and the
state of its implementation and testing in LAL.
Amaldi 4
Abstracts
Page 47
FUTURE DETECTORS - Friday
WILL
C. M. Will
Washington University
Testing Gravity using Current and Future Gravitational-wave Detectors
The regular observation of gravitational radiation by a world-wide network of resonant and laserinterferometric detectors will usher in a new form of astronomy. At the same time, it will provide new and
interesting tests of general relativity. We review the current empirical status of general relativity, and
discuss three areas in which direct observation of gravitational radiation could test the theory further:
polarization of the waves, speed of the waves, and back-reaction of the waves on the evolution of the
source.
OPERATING DETECTORS - Tuesday
WILLKE
B. Willke
Inst. f. Atom- und Molekuelphysik
Status of GEO
The German/British GEO600 project is currently commissioning a laser interferometric gravitational wave
detector with 600m arm length near Hannover/Germany. A short project review will be followed by a
status report on the different detector subsystems with special emphasis on the laser, mode cleaners and the
first monolithic suspensions installed recently.
ISOLATION and SUSPENSION - Wednesday
WINTERFLOOD
J. Winterflood, D.G. Blair
The University of Western Australia
High Performance Vibration Isolation Using Springs in Euler Column Buckling Mode
A revolutionary new suspension technique using mechanical springs in a new manner will be presented
which reduces the mass of suspension springs for small motions to their ultimate minimum (by typically
three orders of magnitude), greatly increasing the resonant frequency of internal modes and vastly reducing
the internal mode coupling.
POSTER
WOODINGS
S. Woodings, R. Burman and D. Blair
The University of Western Australia
The Local Rate Density of Core-Collapse Supernovae
Rates of core-collapse supernovae out to the Virgo cluster are calculated using optical rates, galaxy counts,
galaxy morphology and extinction by the Milky Way, confirming a previous finding of 6 per year. Since
the local mass density is larger than that in the Universe as a whole, the universal current epoch rate density
of supernovae is smaller than the local rate density by an order of magnitude
ISOLATION and SUSPENSION - Wednesday
YAMAMOTO
K. Yamamoto, S. Otsuka, M. Ando, K. Kawabe and K. Tsubono,
University of Tokyo
Study Of The Thermal Noise Caused By Inhomogeneously Distributed Loss
Amaldi 4
Abstracts
Page 48
Recently, new methods to estimate the thermal noise of mechanical oscillators were developed. When the
loss is distributed inhomogeneously, the calculations of these new methods are not consistent with the
estimation obtained from the normal-mode expansion which is the commonly used method to calculate the
thermal noise of mechanical oscillators. We have measured the thermal motions of oscillators with the
inhomogeneous loss and confirmed that the new methods are valid. These are the first experimental results
which show that mode expansion is invalid. We have calculated the thermal noise of the mirror with
inhomogeneous loss in interferometric gravitational wave detectors using these new methods. The results
proved that the loss in the reflective coating is a serious problem. On the contrary, the thermal fluctuation
caused by glued magnets is negligible.
POSTER
ZAKHAROV
A.F. Zakharov
Institute of Theoretical and Experimental Physics, Moscow
Influence Of Gravitational Lensing On Sources Of Gravitational Radiation
In a recent paper by Wang, Turner and Stebbins (1996) an influence of gravitational lensing on increasing
an estimated rate of gravitational radiation sources was considered. We show that the authors used the
incorrect model for this case and thus they gave overestimated rate of possible events for possible sources
of gravitational radiation for the advanced LIGO detector. We show also that if we would use a more
correct model of gravitational lensing, one could conclude that more strong influence on increasing rate of
estimated events of gravitational radiation for advanced LIGO detector could give gravitational lenses of
galactic masses but not gravitational lenses of stellar masses as Wang et al. concluded. Moreover, binary
gravitational lenses could give essential distortion of gravitational wave form template, especially
gravitational wave template of periodic sources and the effect could be significant for templates of quasiperiodic sources which could be detected by a future gravitational wave space detector like LISA.
LASERS and OPTICS - Thursday
ZAWISCHA
I. Zawischa, M. Brendel, M. Frede, R. Wilhelm, C. Fallnich, H. Welling, V. Quetschke, M. Kirchner, B.
Willke, K. Danzmann
Laser Zentrum Hannover
The GEO600 Prestabilized Laser
For interferometric gravitational wave detectors high optical power, single frequency lasers with high
amplitude and frequency stability are needed as input light source. For GEO600 a stable planar,
longitudinally pumped 12W rod oscillator is injection locked to a monolithic 800 mW non-planar ring
oscillator (NPRO). Frequency control signals that are derived at the mode cleaners are fed back to the
NPRO that determines the laser frequency. An intensity noise suppression that acts on the slave pump
diodes is under development. Additionally a combined Nd:YAG-Nd:YVO4 system has been developed that
increases output power from 12 W to over 20 W.
RESONANT MASS DETECTORS - Friday
ZENDRI
J.-P Zendri for the AURIGA collaboration
INFN – Laboratori Nazionale di Legnara
Status Report And Near Future Prospects For The GW Detector AURIGA
We describe the experimental efforts to set up the next AURIGA run. Thanks to the up-graded capacitive
readout, fully characterized and optimized in the transducer test facility, we estimate that the resulting
sensitivity and bandwidth will improve by at least one order of magnitude. The experience achieved on the
test facility has been useful also to design a new cryogenic mechanical attenuation system for AURIGA.
Amaldi 4
Abstracts
Page 49
POSTER
ZWEIZIG
J. Zweizig
LIGO California Institute of Technology
The LIGO Global Diagnostics System and Program of Engineering Runs
The LIGO Global Diagnostics (GDS) group has developed a computing infrastructure for use in
characterizing the LIGO interferometers and monitoring running conditions and the quality of data
produced. The GDS software and hardware facilities are being tested, and their development is being
guided by a series of engineering runs. The engineering run program has been designed to use an
increasing fraction of the LIGO apparatus to investigate aspects of the detector that may only be tested by a
prolonged, coordinated running. The runs also provide an opportunity to develop the operational
procedures to be used for the completed inteferometers. This paper gives a brief description of the
diagnostic and monitoring facilities provided by the GDS, and some results from recent engineering runs.
Amaldi 4
Abstracts
Page 50