SAGENAP Review of the XENON Project
March 12-13, 2002
The XENON Project
A 1 tonne Liquid Xenon experiment for a sensitive
Dark Matter Search
Elena Aprile
Physics Department, Columbia University
Elena Aprile
1
SAGENAP Review of the XENON Project
March 12-13, 2002
The XENON Project Overview
Outline
 Science Motivation and Goals Overview
 Dark Matter Direct Searches Worldwide
 LXe Properties relevant to WIMP Detection
 XENON Instrument Design Overview
 Comparison with other LXe Projects
 XENON Team Presentations
 XENON Organization and Management
Elena Aprile
2
The XENON Collaboration
Columbia University: E. Aprile (Principal Investigator)
T. Baltz, A. Curioni, K-L. Giboni, C. Hailey, L. Hui, M. Kobayashi and K. Ni
Brown University: R. Gaitskell
Princeton University: T.Shutt
Rice University: U. Oberlack
LLNL: W. Craig
Elena Aprile
3
Why should NSF support XENON
• Because a WIMP experiment with discovery potential will have
enormous scientific impact in particle physics and astrophysics.
Need to validate discovery with different targets and technology.
• Because the timing is right and the proposed XENON concept is
based on a relatively simple technology with unique suitability for
the 1-tonne scale required by the science.
• Because the proposing team combines extensive experience
with large scale LXe detectors with complementary experience in
other key areas required for a successful realization of the
XENON dark matter project!
Elena Aprile
4
The Case for Non-Baryonic Dark Matter
• Standard BBN calculations + 4He and D primordial abundance
Ωbh2 = 0.020 ± 0.001
(APJ, 552, L1, 2001)
• Measurements of the matter density
Ωm = 0.2 ~ 0.4
h=H0/100 kms -1Mpc-1 (h = 0.6 ~ 0.8)
•
•
•
•
Cluster velocity dispersion (Mass to Light ratio)
Galactic rotation curves
Cluster baryon fraction from X-ray gas
CMB anisotropies give Ωmh2 = 0.15 ± 0.05 (APJ, 549, 669, 2001)
and also confirms Ωbh2 ~ 0.02
Ωm >> Ωb
Elena Aprile
5
Non-baryonic Dark Matter Candidates
Neutrinos: hard to make up a significant fraction of mass density with
neutrinos, unless much more massive than observed
m < 0.1 eV ( PRL 81(1998)1562)
Axions: strong CP, m ~ 10-5eV, search is in progress using microwave
cavities ( PRL 80(1998)2043)
Massive Compact Halo Objects (MACHO): with 10-7 10 Mo cannot account for a large fraction of the DM in the Milky Way halo
(ApJ 550(2001)L169)
Weakly Interacting Massive Particles (WIMPS):
Stable (or long lived) particles left over from the BB, decoupling when nonrelativistic: their relic density ΩXh2 ~ 1/<X v>
(X ~ weak)  ΩXh2 ~ 1
Elena Aprile
6
Supersymmetry
• Stabilizes MPL and MZ hierarchy
• Unification of coupling constants
• Lightest Super Particle is stable
SUSY offers the favorite WIMP candidate
• Neutralino
~ ~0
~0
~
      1   2
Superposition of photino, zino and higgsinos
• SUSY particles were not invented to solve the dark matter problem.
• Particles with several 100 GeV/c2 actively being pursued at accelerators.
• Direct WIMP searches can probe mass values impossible to reach at colliders.
• Typical WIMP nucleon cross sections in the range 10-5 and 10-11 pb
Elena Aprile
7
Muon g-2 Measurement
• BNL results on muon
anomalous magnetic moment
disagree with Standard Model
at 1.6  level (PRL
86(2001)2227)
• If discrepancy is due to SUSY,
a large neutralino-nucleon cross
section (10-9 pb) and a low mass
(<500 GeV) are favored
• World eagerly awaiting for new
results from last run!
Elena Aprile
8
WIMP Direct Detection
• Elastic scattering off nuclei in
laboratory target
 measure nuclear recoil energy
• Spin-independent interactions are coherent ( A2) at low energy 
dominate for most models. Target with odd isotopes needed for spindependent interactions
• Energy spectrum and rate depend on local dark matter density 0 :
measured galactic rotation curve : flat out to 50 kpc with vcir220 km/s 
spherical halo with 0  0.3-0.5 GeV/cm3 and M-B velocity distribution
with v 220 km/s
Elena Aprile
9
Experimental Challenges
• Recoil energy is small  few keV 
detectors with low threshold
• Event rates are low << radioactive
background 
detectors with low radioactivity, deep
underground and with active
background rejection
With E0 = 1/2MX(0c)2
R0 c2 ER / E0 r 2
dR
 c1 (
)e
F ( ER )
dER
E0 r
r = 4 MX MA /(MX+ MA )2
R0 = T0c0
c10.78 and c20.58
F=form factor (see
Phys.Rept.267(1996)195
Elena Aprile
10
Background Rejection Methods
• Reject events more likely to be due to , e,  radioactivities
 multiple-scatters (WIMPs interact too weakly) HDMS
 single-scatters localized near detector walls (WIMPs interact
anywhere) CDMS ZIP detectors
 electron recoils (WIMPs more likely interact with nucleus)
CDMS, EDELWEISS (CRESST, ZEPLINs, DRIFT)
A 3D LXeTPC like XENON will combine all these rejection capabilities
• Use motion of Earth/Sun through WIMP halo
 direction of recoil DRIFT
 annual modulation  DAMA, NAIAD
Elena Aprile
11
Expected rates for various targets
For a heavy target nucleus such as Xe, a very low recoil energy threshold is crucial.
The expected rate, integrated above threshold of ~16 keV is 1 events/ kg/day
Elena Aprile
12
WIMP Direct Searches with Recoil Discrimination
Project
Detectors
Active Mass
Rejection Method
Location( mwe)
Timescale
CDMS II
Si and Ge
2 kg (Si) +5 kg (Ge)
Phonon and Charge
Soudan (2200)
2002 – 2007
1 tonne
CryoArray
EDELWEISS I
Ge
3 X 320 g ~ 1 kg
EDELWEISS II
CRESST II
CaWO4
21 X 320 g ~ 7 kg
33 X 300 g ~10 kg
ZEPLIN II
LXe
30 kg
LXe
1 tonne
6 kg
ZEPLIN-MAX
XMASS
LXe
1 tonne
1 kg
XENON
LXe
20kg
10 kg
ZEPLIN IV
ZEPLIN III
DRIFT 1 , 2
DRIFT 3
Elena Aprile
CS2
Start 2006 ?
Phonon and Charge
Frejus (4600)
2002 - 2004
Phonon and
Scintillation
Charge and scintillation
Gran Sasso (3800)
Start 2004 ?
300 g setup 2002
Boulby (3300)
Construction 2001
Boulby (3300)
Start 2007 ?
Construction 2001
Charge and scintillation
Kamioka (2600)
Start 2006 ?
Installed 2001
Charge and scintillation
Homestake (>4000)
Construction 2002
Operational 2004
Charge and scintillation
100 kg
Start 2005 ?
1 tonne
< 1 kg
Start 2007 ?
Installed 2001
100kg
Recoil direction
Boulby (3300)
Start 2004 ?
13
Current and Projected Limits of
Spin-Independent WIMP Searches
•
Projection for CDMS Soudan (7kg
Ge+Si) and competing experiments in
Europe, including LXe projects of the
UKDM program is ~1 event / kg / yr
•
It will take a target mass at 1 tonne
scale and similar background
discrimination power to reach a
sensitivity of ~1 event / 100kg / yr or
 ~ 10-46 cm2
•
LXe attractive target for scale-up.
Projection for XENON based on
Homestake, 99.5% recoil
discrimination, 16 keV true recoil
energy threshold and an overall 3.9x
10-5 cts /kg /d /keV background rate.
Elena Aprile
14
Why is Liquid Xenon Attractive for Dark Matter

High mass Xe nucleus good for scalar interaction of WIMPs

High atomic number (Z=54) and density (r=3g/cc) good for compact and flexible detector
geometry. “Easy” cryogenics at –100C

High ionization (W=15.6eV) yield and small Fano factor for good E/E

High electron drift velocity (v=2 mm/ms) and low diffusion for excellent spatial
resolution. Calorimetry and 3D event localization powerful for background rejection
based on fiducial volume cuts and event multiplicity

High scintillation (W~13 eV) yield with fast response and strong dependence on ionizing
particle for event trigger and background discrimination with PSD

Distinct charge/light ratio for electron/nuclear energy deposits for high background
discrimination

Available in large quantity and “easy” to purify with a variety of methods. Demonstrated
electron lifetime before trapping of order 1 millisecond for long drift. No long-lived
radioactive isotopes. 85Kr contamination reducible to ppb level
Elena Aprile
15
… and for Solar n and 0n Decay
124
Xe
126
Xe
128
Xe
129
Xe
130
Xe
131
Xe
132
Xe
134
Xe
136
Xe
(0.10%) (0.09%) (1.92%) (26.4%) (4.07%) (21.2%) (26.9%) (10.4%) (8.87%)
Mostly Odd
Mostly Even
-nucleus
Separation here
Odd enriched
 Solar neutrino
 Dark matter Spin dependent
X M A SS
LXe prototype in Kamioka
Elena Aprile
Even enriched:containing 136Xe
 2n/0n
 Dark matter Spin independent
EXO
LXe prototype at Stanford
16
Ionization and Scintillation in Liquid Xenon
I/S (electron) >> I/S (non relativistic particle)
L/L0 or Q/Q0 (%)
Alpha scintillation
Electron charge
electron scintillation
Alpha charge
Electric Field (kV/cm)
Elena Aprile
17
Electron vs Nuclear Recoil Discrimination
(Direct & Proportional Scintillation )
Measure both direct
scintillation(S1) and charge
(proportional scintillation) (S2)
Nuclear recoil from
•WIMP
•Neutron
Electron recoil from
•gamma
•Electron
•Alpha
Proportional scintillation
depends on type of recoil and
applied electric field.
electron recoil → S2 >> S1
nuclear recoil → S2 < S1
but
detectable
if E large
Elena
Aprile
Dual Phase Detection Principle
Common to All LXe DM Projects
Gas
anode
grid
Liquid
cathode
18
The XENON Experiment : Design Overview
Elena Aprile
•
The XENON design is modular.
An array of 10 independent 3D position
sensitive LXeTPC modules, each with
a 100 kg active Xe mass, is used to
make the 1-tonne scale experiment.
•
The fiducial LXe volume of each
module is self-shielded by additional
LXe. The thickness of the active shield
will be optimized for effective charged
and neutral background rejection.
•
One common vessel of ~ 60 cm
diameter and 60 cm height is used to
house the TPC teflon and copper rings
structure filled with the 100 kg Xe
target and the shield LXe (~50 kg ).
19
The XENON TPC: Principle of Operation
•
•
•
•
•
Elena Aprile
30 cm drift gap to maximize active
target  long electron lifetime in LXe
demonstrated
5 kV/cm drift field to detect small
charge from nuclear recoils  internal
HV multiplier (Cockroft Walton type)
Electrons extraction into gas phase to
detect charge via proportional
scintillation (~1000 UV /e/cm)
demonstrated
Internal CsI photocathode with
QE~31% (Aprile et al. NIMA
338,1994) to enhance direct light
signal and thus lower threshold 
demonstrated
PMTs readout inside the TPC for
direct and secondary light  need
PMTs with low activity from U/Th/K
20
The XENON TPC Signals
•
•
•
Three distinct signals associated with typical event. Amplification of primary
scintillation light with CsI photocathode important for low threshold and for
triggering.
Event depth of interaction (Z) from timing and XY-location from center of gravity of
secondary light signals on PMTs array.
Effective background rejection direct consequence of 3D event localization (TPC)
Elena Aprile
21
Detection of LXe Light with a
CsI Photocathode
• Stable performance of reflective
CsI photocathodes with high QE
of 31% in LXe has been
demonstrated by the Columbia
measurements
• CsI photocathodes can be made
in any size/shape with uniform
response, and are inexpensive.
• LXe negative electron affinity
Vo(LXe)= - 0.67 eV and the
applied electric field explain the
favorable electron extraction at
the CsI-liquid interface.
Elena Aprile
Aprile et al. NIMA 338(1994)
Aprile et al. NIMA 343(1994)
22
Light Collection Efficiency: MonteCarlo
Assumptions








Wph : 13 eV
lph: 1.7 m
Quenching Factor: 25%
Q.E. of PMTs: 26%
Q.E. of CsI : 31%
R.E of Teflon Wall: 90%
Mass of Liquid Xe: 100 kg
37 PMTs (2 inch) array
Elena Aprile
23
Simulation Results
•
A 16 keV (true) nuclear recoil gives ~ 24
photoelectrons. The CsI readout
contributes the largest fraction of them.
•
Multiplication in the gas phase gives a
strong secondary scintillation pulse for
triggering on 2-3 PMTs.
•
Coincidence of direct PMTs sum signal
and amplified light signal from CsI
•
Main Trigger is the last signal in time
sequence post-triggered digitizer read
out Trigger threshold can be set very low
because of low event rate and small
number of signals to digitize. PMTs at
low temperature low noise.
•
Even w/o CsI (replaced by reflector)
we still expect ~6 pe . Several
possible ways to improve light
collection.
Elena Aprile
24
Summary of Previous Nuclear Recoil
Measurements (Quenching Factor)
 previous measurements have wide scatter
 no measurements at all at low energies
 results consistent with Lindhard theory
Elena Aprile
25
We have experience measuring neutron-nuclear
recoil efficiency
typical setup for measurement of
nuclear recoil scintillation efficiency
at University of Sheffield
measured low energy nuclear recoil efficiency of
liquid scintillator
2.9 MeV neutron beam
Elena Aprile
Hong, Hailey et. al., J. AstroParticle Physics 2001
26
Why Do Nuclear Recoil Scintillation Efficiency
Measurements?
• Confirm that measured efficiency at higher energies extends down to
lowest energies of interest to a WIMP search
• Confirm result in our particular experimental configuration.
Results can vary with Xe purity, light collection efficiency etc.
• Measure true nuclear recoil scintillation pulse shapes
Elena Aprile
27
Charge readout with GEMs:
a promising alternative
•
•
•
High gain in pure Xe with
3GEMs demonstrated
Coating of GEMs with CsI
2D readout for mm resolution
See Bondar et al.,Vienna01
Elena Aprile
28
XENON Technical Heritage: LXeGRIT
A 30 kg Liquid Xenon Time Projection Chamber developed
with NASA support. 3D imaging detector with good
spectroscopy is the basis of the balloon-borne LXeGRIT, a novel
Compton Telescope for MeV Gamma- Ray Astrophysics.
 The LXeTPC operation and response to gamma-rays
successfully tested in the lab and in the harsh conditions of a
near space environment.
 Road to LXeGRIT: extensive R&D to study LXe ionization
and scintillation properties, purification techniques to achieve
long electron drift for large volume application, energy
resolution and 3D imaging resolution studies, electron mobility
etc.

Elena Aprile
29
A Liquid Xenon Time Projection Chamber for
Gamma-Ray Astrophysics
Elena Aprile
30
The Columbia 10 liter LXeTPC
• 30 kg active Xe mass
• 20 x 20 cm2 active area
• 8 cm drift with 4 kV/cm
• Charge and Light readout
• 128 wires/anodes digitizers
• 4UV PMTs
Elena Aprile
31
High Purity Xenon for Long Electron Drift
and Energy Resolution
And the power of Compton Imaging
Elena Aprile
32
Compton Imaging of MeV -ray
Sources
Elena Aprile
33
3D capability for event discrimination:
Flight Data
Elena Aprile
34
From the Lab to the Sky: The Balloon-Borne Liquid
Xenon Gamma-Ray Imaging Telescope (LXeGRIT)
Atm/Cosmic Diffuse MC simulation and Data
Elena Aprile
Compton Imaging Events
35
Background Considerations for XENON
•  and  induced background
(1/2=10.7y): 85Kr/Kr  2 x 10-11 in air giving ~1Bq/m3
Standard Xe gas contains ~ 10ppm of Kr10 Hz from 85Kr decays in 1 liter of LXe.
Allowing <1 85Kr decay/day i n XENON energy band  <1 ppb level of Kr in Xe
85Kr
136Xe
2n decay (1/2=8 x 1021y): with Q= 2.48 MeV expected rate in
XENON is 1 x 10-6 cts/kg/d/keV before any rejection
• Neutron induced background
Muon induced neutrons: spallation of 136Xe and 134Xe  take 10 mb and Homestake
4.4 kmwe estimate 6 x 10-5 cts/kg/d before any rejection
 reduce by muon veto with 99% efficiency
(,n) neutrons from rock: 1000/n/m2/d from (,n) reactions from U/Th of rock
 appropriate shield reduces this background to 1 x 10-6 cts/kg/d/keV
Neutrons from U/Th of detector materials: within shield, neutrons from U/Th of
detector components and vessel give 5 x 10-5 cts/kg/d/keV
 lower it by x10 with materials selection
Elena Aprile
36
Background Considerations for XENON
•  -rays from U/Th/K contamination in PMTs and detector
components dominate the background rate. For the PMTs contribution we have
assumed a low activity version of the Hamamatsu R6041 (  100 cts/d ) consistent
with recent measurements in Japan with a Hamamatsu R7281Q developed for the
XMASS group (Moriyama et al., Xenon01 Workshop).
Numbers are based on Homestake location and reflect 99.5% background
rejection but no reduction due to 3D imaging and active LXe shield.
Elena Aprile
37
How is XENON different from other
Liquid Xe Projects?
Elena Aprile
38
UCLA ZEPLIN II
Elena Aprile
39
ZEPLIN II
Elena Aprile
40
ZEPLIN II  ZEPLIN IV
30 kg  1000 kg
The latest design as at
DM2002
Elena Aprile
41
UKDM ZEPLIN III
Elena Aprile
42
ZEPLIN III
Elena Aprile
43
The LXe Program at Boulby
Elena Aprile
44
The LXe Program at Kamioka
XMASS
Cold finger
present
with new PMTs no rejec.
gas filling line
Wire set
(Grid1,Anode
Grid2)
with 99% rejection
PTFE Teflon
(Reflector)
Gas Xe
MgF2 Window
with Ni mesh
(cathode)
OFHC vessel
(5cm)
Elena Aprile
Liq. Xe(1kg)
9.5 cm Drift
PMT
45
Signals from 1kg XMASS Prototype
42000photon/MeV
Decay time 45nsec
direct
direct
direct
drift time
Elena Aprile
proportional
proportional
drift time
46
Proportional scintillation(S2)
XMASS Recoil /γ ray Separation
>99% γ ray rejection
22 keV gamma ray
Recoil Xenon (neutron source)
Direct scintillation(S1)
Elena Aprile
(Ref. JPS vol.53,No 3,1998, S.Suzuki)
47
XMASS: low activity PMT development
counts
57
Co (122keV)
σ/E = 15 %
2.4 [p.e./keV] at 250[V/cm]
with R7281MgF2 (Q.E.30%)
(HAMAMATSU(prototype)
662keV
p.e.
Towards a 20 kg Detector
counts
137Cs
A low activity version of this tube shows
~4.5× 10-3 Bq!
p.e.
Elena Aprile
48
Answer to Question
• LXe long recognized as promising WIMP target for a large scale experiment with
relatively simple technology. So far however development effort has been subcritical.
• Low energy threshold and background rejection capability yet to be fully
demonstrated.
• Recent move to an underground lab - 1 kg XMASS detector in Kamioka- an
important milestone. Scale up to a 20 kg detector of same design (7 PMTs vs 1) started.
• UCLA ZEPLIN II is similar in size and design to XMASS: drift in LXe over ~ 10 cm
with low electric. Secondary light pulse from low energy nuclear recoils hard to
detect. Scale up to 1 tonne with a monolithic detector (ZEPLIN IV) too risky and
unpractical.
• UKDM ZEPLIN III better discrimination power and lower threshold due to high
electric field. Design does not present an easy scale up from 6 kg to sizable modules of
order 100 kg.
• XENON combines the best of the techniques with a design which can be easily
scaled. Strength of experience with a 30 kg LXeTPC for gamma ray astrophysics +
critical mass at Columbia with collaborators key experiences in DM searches.
Elena Aprile
49
XENON Phase 1 Study: 10 kg Chamber
• Demonstrate electron drift over 30 cm
(Columbia)
• Measure nuclear recoil efficiency in LXe
(Columbia)
• Demonstrate HV multiplier design (Columbia)
• Measure gain in Xe with multi GEMs (Rice and
Princeton)
• Test alternative to PMTs, i.e. LAAPDs (Brown)
• Selection and test of detector materials (LLNL)
• Monte Carlo simulations for detector design and
background studies (Columbia /Princeton/Brown)
• Study Kr removal techniques (Princeton)
• Characterize 10 kg detector response and with 
and neutron sources (Entire Collaboration)
Elena Aprile
50
What next? XENON and NUSL
• The result of the 2yr Phase 1 will be a
Muon flux vs overburden
10
6
10
5
10
4
Proposed NUSL Homestake
Current Laboratories
WIPP
Soudan
• By this time the situation of a NUSL will
be clear. If NUSL is delayed, several
alternative locations possible ( Boulby, GS,
WIPP, etc.)…but deeper the better..
Muon Intensity, m-2
• Phase 2 is for construction and operation
of a 100 kg module as 1st step towards 1
tonne. We plan to seek DOE and NSF
support and more collaborators
y
-1
working 10 kg prototype with demonstrated
low ER threshold and recoil discrimination
capability. Its move to a deep underground
location will initiate science return.
Kamioka
Gran Sasso
10
3
10
2
Homestake
(Chlorine)
Baksan
Mont Blanc
Sudbury
NUSL - Homestake
10
1
5
6
7
8
9
10
3
2
3
4
5
6
7
10
Depth, meters water equivalent
Elena Aprile
8 9
51
4
Summary
• Liquid Xenon is an excellent detector material well suited for the large
target mass required for a sensitive Dark Matter experiment.
• The XENON experiment is proposed as an array of ten independent, self
shielded, 3D position sensitive LXeTPCs each with 100 kg active mass.
• The detector design, largely based on established technology and >10 yrs
experience with LXe detectors development at Columbia, maximizes the
fiducial volume and the signal information useful to distinguish the rare
WIMP events from the large background.
• With a total mass of 1-tonne, a nuclear recoil discrimination > 99.5% and
a threshold of ~ 16 keV, XENON expected sensitivity of  0.0001
events/kg/day in 3 yrs operation, will cover most SUSY predictions.
Elena Aprile
52
XENON Organization
Subsystem responsibility is allocated amongst the
team of experienced co-investigators.
Elena Aprile
53
XENON Management Approach
• Phase I of the XENON project spans a 2 year period from the funding
start date. This instrument development effort has the focused goal of a
clear demonstration of the capabilities of a 10 kg LXe detector for a
sensitive Dark Matter search.
• The 10 kg prototype defines the roadmap to the Phase II development of
a 100 kg detector as one unit of a 1 tonne scale XENON experiment.
• In complexity, the XENON Phase I development does not exceed the
NASA funded LXeGRIT experiment and we adopt the successful
practices developed during this project.
•
We have the required critical mass with extensive expertise in LXe
detector technology and other areas relevant to a Dark Matter
experiment. This, plus sensible management practices will insure
meeting the milestones promised by the end of the 2nd year of Phase I.
Elena Aprile
54
Management Activities
To coordinate the efforts and insure the appropriate level of
communication and exchange of information between the
Columbia team and team members at Brown, Princeton,
Rice, and LLNL the PI will:
–
–
–
–
–
–
Elena Aprile
organize bi-weekly videoconference meetings
obtain monthly progress reports on all sub systems
organize semi annual project reviews with participation of
collaborators and external advisors
prepare yearly progress reports for NSF
encourage student/minority involvement in the research
take full responsibility for the key deliverables to NSF by end of
Phase I
55
Development Schedule
Year 1 activities
concentrate on:
• Monte Carlo simulations to guide
the design
• Gas system construction and
testing
• Neutron recoil efficiency
measurements
• Baseline detector development
• Alternative detector development
• Materials selection and testing
Elena Aprile
56
Development Schedule (2)
Year 2 activities
concentrate on:
• Build of the 10kg prototype
• Demonstration of Krypton
reduction
• Design of the 100kg instrument
End of Phase I results in
near final design of
100kg module and
demonstration of all key
technologies in the 10 kg
prototype.
Elena Aprile
57
Team Members Expertise
Name
Institution
Main Expertise
Other Experiments
Elena Aprile
Columbia
LXeGRIT
XENA
Chuck Hailey
Columbia
Karl Giboni
Columbia
Masanori Kobayasi
Columbia
Uwe Oberlack
Rice
(formerly
Columbia)
Tom Shutt
Princeton
William Craig
LLNL
(formerly
Columbia)
Brown
Liquid rare gas detectors
Ionization and scintillation
Time projection chambers
Imaging detectors
X-ray Proportional scintillation
counters
Scintillators
Hard X-ray focusing optics
Imaging detectors
Time Projection Chambers
Room temp. semiconductors
Analog and Digital Electronics
Germanium Detectors
LXe Time Projection Chamber
Imaging detectors data analysis
Data acquisition
Imaging detectors data analysis
Event reconstruction techniques
LXe Time Projection Chamber
Low noise electronics
Cryogenic detectors
Low radioactivity materials
Monte Carlo background studies
Project management
System engineering
Instrument development
Cryogenic detectors
Low noise electronics
Monte Carlo background studies
Richard Gaitskell
Elena Aprile
HEFT
ZEPELIN III
LXeGRIT
XENA
SELENE
LXeGRIT
COMPTEL
LXeGRIT
CDMS
Borexino
DRIFT
HEFT
CDMS
CryoArray
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Budget Details
Year 1 request 823k$
7%
Year 2 request 873k$
16%
Senior Personnel
Other Labor
28%
M&S
24%
Travel
Subcontracts
2%
Indirect
23%
Budget breakout (of 2 year total) is consistent with our
fast track development of a working prototype
Elena Aprile
59
Team Members Presentations
Elena Aprile
60
Materials Selection and Testing
Bill Craig (LLNL)
• Candidate material selection will begin with study of
existing databases assembled for other projects.
• LLNL personnel (Craig, Ziock) are associated with ongoing
projects requiring low background and will use this existing
infrastructure to do testing of candidate materials.
• Close coupling between this effort and the XENON 10/100
kg design team to ensure optimal material choices are
incorporated as quickly as possible.
Elena Aprile
61