kilometer-scale neutrino
observatories
AMANDA: Proof of Concept
• since 1992 we have deployed 24 strings
with more than 750 photon detectors
(basically 8-inch photomultipliers).
• R&D detector for proof of concept: 375
times SuperK instrumented volume with
1.5% the total photocathode area.
• IceCube: 45 times AMANDA II
instrumented volume with 7 times the
total photocathode area.
IceCube
IceTop
South Pole
Runway
• 80 Strings
• 4800 PMT
• Instrumented
volume: 1 km3
(1 Gton)
AMANDA
1400 m
• IceCube is designed
to detect neutrinos
of all flavors at
energies from 107
eV (SN) to 1020 eV
2400 m
South Pole
AMANDA– 1 mile deep
South Pole
Dark sector
Skiway
AMANDA
Dome
IceCube
Planned Location 1 km east
South Pole
Dark sector
Skiway
AMANDA
Dome
IceCube
µ-event in
IceCube
300 atmospheric
neutrinos per day
AMANDA II
IceCube:
-> Larger telescope
-> Superior detector
1 km
Muon Events
Eµ= 6 PeV
Eµ= 10 TeV
Measure energy by counting the number of fired PMT.
(This is a very simple but robust method)
Cherenkov light from muons and cascades
muon
Reconstruction
cascade: e or t
• Maximum likelihood method
• Use expected time profiles of photon flight
times
AMANDA
Event
Signatures:
Cascades
 CC electron and tau
neutrino interaction:
(e,t,) + N  (e, t) + X
 NC neutrino interaction:
x + N  x + X
Cascades
Cascade event
• the length of the
e- cascade is small
compared to the
spacing of sensors.
• roughly spherical
density distribution
of light.
• 1 PeV ≈ 500 m
diameter, additional
100 m per decade
of energy
• linear energy
resolution
e + N --> e- + X
Energy = 375 TeV
PeV
t
(300m)
t t
t decays
Neutrino flavor
Neutrino ID (solid)
Energy and angle (shaded)
•Filled area: particle id, direction, energy
•Shaded area: energy only
enhanced role of tau neutrinos:
• cosmic beam: e = m = t
because of oscillations
• t
not absorbed by the Earth
(regeneration)
• pile-up near 1 PeV
where ideal sensitivity
IceCube
• start 02
• first strings 04
• completed 09
Drilling
Amanda (3-reel) and ICECUBE (1-reel) Drill
Drilling
ICECUBE
Schedule and Cost
03-04
04-05
05-06
06-07
07-08
08-09
09-10
drill equipment to Pole
first strings
(proof that 16/season are feasible,
prepare 10 full strings)
16 strings
16 strings
16 strings
16 strings
remaining strings
Overall cost with personnel, contingency, overhead: ~ 250 M$
Detector: ~ 55 M$
Logistics, including drilling: ~ 40 M$
evolution of read-out strategy
- timing
- dyn. range
- no x-talk
- easy
calibration
- cost
- robustness
- dynamic
range
01/02 - 03/04: Equipping all Amanda channels with FADCs to get full
waveform information (IceCube compatibility)
 better reconstruction, particularly cascades and high energy tracks
Assembled DOM
IceCube has been designed as a
discovery instrument with improved:
• telescope area ( > 1km2 after all cuts)
• detection volume ( > 1km3 after all cuts)
• energy measurement:
secondary muons ( < 0.3 in ln E) and
electromagnetic showers ( < 20% in E)
• identification of neutrino flavor
• Sub-degree angular resolution
(< unavoidable neutrino-muon misalignment)
AMANDA
• AMANDA collected > 3,000 ’s
• 4 more every day on-line
• neutrino sensitivity has reached  = g
• > 300,000 per year from IceCube
• race for solving the CR puzzle is on!
conclusions
• nu astronomy reached ~ 0.1 km2year
• will reach km-scale in < 5 years
• northern hemisphere detectors soon
• EeV detectors over similar time scale
• if history repeats, I did not tell
you about the science !!!
The IceCube Collaboration
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Bartol Research Institute, University of Delaware
BUGH Wuppertal, Germany
Universite Libre de Bruxelles, Brussels, Belgium
CTSPS, Clark-Atlanta University, Atlanta USA
DESY-Zeuthen, Zeuthen, Germany
Institute for Advanced Study, Princeton, USA
Dept. of Technology, Kalmar University, Kalmar, Sweden
Lawrence Berkeley National Laboratory, Berkeley, USA
Department of Physics, Southern University and A\&M College, Baton Rouge, LA, USA
Dept. of Physics, UC Berkeley, USA
Institute of Physics, University of Mainz, Mainz, Germany
Dept. of Physics, University of Maryland, USA
University of Mons-Hainaut, Mons, Belgium
Dept. of Physics and Astronomy, University of Pennsylvania, Philadelphia, USA
Dept. of Astronomy, Dept. of Physics, SSEC, PSL, University of Wisconsin, Madison, USA
Physics Department, University of Wisconsin, River Falls, USA
Division of High Energy Physics, Uppsala University, Uppsala, Sweden
Fysikum, Stockholm University, Stockholm, Sweden
University of Alabama, Tusceloosa, USA
Vrije Universiteit Brussel, Brussel, Belgium
Chiba University, Japan
Imperial College London, UK
Utrecht University, Utrecht, The Netherlands
Universidad Simon Bolivar, Caracas, Venezuela
University of Canterbury, Christchurch, New Zealand
super-EeV detectors
GZK Cosmic Rays & Neutrinos
• cosmogenic
neutrinos
are guaranteed
• fluxes may be larger
for some models, such
as topological defects
p + gCMB  p + n
Radio Emission from neutrinoinduced electromagnetic cascades
• Electromagnetic cascades: electron-positron pairs and
(mostly) gammas  electrically neutral, no radio emission.
• Compton scattering of photons on atomic electrons creates
negative charge excess of ~ 20%
• Negative charge radiates coherently at MHz ~ GHz 
Power = Energy 2
• Askarian effect demonstrated at SLAC: consistent with
calculations
RICE
Radio Detection in South Pole Ice
Neutrino enters ice
Neutrino interacts
Antenna
& Cable
• Installed ~15 antennas
few hundred m depth with
AMANDA strings.
• Tests and data since 1996.
• Most events due to local
radio noise, few candidates.
• Continuing to take data,
and first limits prepared.
• Proposal to Piggyback with
ICECUBE
Cube is .6 km on side
Two cones show 3 dB
signal strength
TauWatch
Using Mountains to Convert ντ
3/02 Workshop in Taiwan, see http://hep1.phys.ntu.edu.tw/vhetnw
also, HiRes, Auger….
ANITA : Radio from EeV ’s in
Polar Ice
•Antarctic
Ice at
f<1GHz, T<-20C
• largest homogenous,
RF-transmissive solid
mass in the world
Antarctic Impulsive Transient
Antenna (ANITA)
M. Rosen, Univ. of Hawaii
Solar
Panels
ANITA
Gondola &
Payload
Antenna array
Cover (partially cut away)
• ANITA Goal: Pathfinding mission for GZK neutrinos
• NASA SR&T start expected this October, launch in
2006
Ocean Acoustic Detection
New Stanford Effort using US Navy Array
US Navy acoustic tracking range in Tongue of the
Ocean, Atlantic
Hydrophones 1550-1600 m deep
pancake beam pattern
G.Gratta, atro-ph/0104033
Summary on Technology
 Over 5 years, Amanda has evolved into a
30.000 m2 neutrino telescope
 Construction and improvement hand in hand
 Developed and tested IceCube technology
 Detailed measurement of ice down to 2.4 km
 Clear record in performance, reliability,
time schedule and cost
 We know that we can build a km3 telescope
Summary Amanda Physics
 Diffuse flux: Best limits. Entering interesting range.
 EHE fluxes:
0.3 km2 at EeV. A-II testing EeV blazar models.
 Point sources: Best limits. Testing first models.
 GRB: sensitivity after 4 years close to predictions
 Relativistic Magnetic Monopoles:
Best limits (0.05 x Parker bound)
 WIMP search: high mass limits ~ Underground limits
 Monitoring Galaxy for SN bursts
 Cosmic Ray Composition at knee
... and IceCube Physics
 Diffuse flux: sensitivity nearly factor 10 below WB limit
 EHE fluxes: IceCube testing some GZK models
 Point sources: sensitivity ~ 10-12 cm-2 s-1 for > 1 TeV
Many models predict up to few tens of events/year
 GRB: 10-100 events per year. Test WB model
 Rel.Magnetic Monopoles: < 1/1000 Parker bound)
 WIMPs: complementary to future direct search expts.
 SN monitoring up to LMC. Triangulation ?
 Cosmic ray composition at knee