IceCube Meeting Berkeley 1March, 23 2005
Alternative Detection Methods for Highest Energy Neutrinos
Possibilities – Timescales - Competition
Rolf Nahnhauer, DESY
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locked MZI with 150 OPDone MZI arm disconnected
IceCube Meeting Berkeley 2March, 23 2005
Projects of the next decade:
All Radiation EeV Neutrino detection Arrays
observe > 10 events/year from GZK flux
Veff ≥ 50 km3
target material: water, ice, salt, rock?
profit from combination of different detections methods:
optical-acoustic-radio
in background reduction, cross calibration, detection sensitivity,…
IceCube Meeting Berkeley 3March, 23 2005
The Water ARENA
+ Acoustic1000 hydrophone array for Mediterranean
3 hydrophones per cluster( sensor distance : 50 m )
300 m grid spacing
red line : incident neutrino (7.2*1019 eV)red cube : deposited energy of - interactionyellow points : hydrophonesgreen cubes : signal hits
From L. Thompson, unpublishedAnd U. Katz, ApPEC Workshop 2003
IceCube Meeting Berkeley 4March, 23 2005
Water ARENA Sensor R&DErlangen :cheap selfmade hydrophones
sensitivity = 6x commercial S/N 10
pressure wave on fibre modulation of cavity size, leading to modulation of laser wavelength detectable by interferometer
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locked MZI with 150 OPDone MZI arm disconnected
spectral response to a 65 kHz loud-speaker modulation
(Mach-Zender OPD = 150 m)
commercial
selfmade
From: P. Kollmannsberger, DPG 2004
From: M.Morganti, Roma 2005
Pisa, Firenze:fibre acoustic sensors
IceCube Meeting Berkeley 5March, 23 2005
A Water ARENA Test Site
cable:10 OF; 6 conductors
A fully equipped facility to test and develop technologies for the Mediterranean km3
From G. Riccobene for this workshop
2004-2006
Shore laboratoryport of Catania
Underwater test site:25 km E offshore Catania
2000 m depth
IceCube Meeting Berkeley 6March, 23 2005
NEMO “phase 1” frame
Successfully deployed on 23 Jan 2005
•4 hydrophones: • 2 (10 Hz - 40 kHz) ; 2 (1 kHz - 40 kHz)•Digitization (24 bits 96 kHz) and electro-optical translation •Continuous monitoring from shore
First tests: The NEMO - ODE (Ocean noise Detection Experiment)
From G. Riccobene for this workshop
Sperm whales clicks
IceCube Meeting Berkeley 7March, 23 2005
The Water ARENAPreparation at Antares site in 2005
Spring deploy string-0, dummy+hydrophonescheck sensitivity, measure noise
Summerrecover string-0Autumn deploy string-1, string-2
each has five levels upper level 5x2 hydrophones
4 lower levels 5x3 PMT’s
Two strong groups: Erlangen , SheffieldMoney: ~2x500k EuroPersonpower (G): 10 students (PhD+diploma)
9 talks at German DPG 2005(1 talk from IC++)
Personpower(UK) ???
IceCube Meeting Berkeley 8March, 23 2005
If LOPES R&D successful add radio detectors to AUGER
4 km 1EeV air shower
radio beam
2 km
50 km
1mV/m/Mhz
1
The Air ARENA
AUGER + Radio
vertical 1017 eV air shower
center+100m+250m
data:Allan and Prah
A. Horneffer et al., SPIE 2004
IceCube Meeting Berkeley 9March, 23 2005
Iran, 7km diameter
Canada 8x5 km2
Many Gulf coast salt domes3-4 km diameters, 5-10 km depths typical
The Salt ARENA Imany big salt domes around the world
From M. Chiba, NANP-Dubna 2003
Typical salt dome: RF loss similar to ice at -40° C 2.5 times more dense build radio detector array
IceCube Meeting Berkeley 10March, 23 2005
Halite (rock salt)• La(<1GHz) > 500 m w.e.• Depth to >10km• Diameter: 3-8 km• Veff ~ 100-200 km3 w.e.• No known background• >2p steradians possible
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Meeting at SLAC Feb/05 :SalSA Collaboration bornU-Hawaii,UCLA, SLAC, …
Basic array geometry simulatedP. Gorham talk at SLAC meeting
2.5 km3 array with 225 m spacing122=144 strings, 123=1728 antenna nodes12 antennas per node, dual polarization ~300 km3 sr at 1 EeVthreshold 1017 eV, few 100s antennas hit at 1 EeV, >1000 hits at 10 EeV
Rate: claim at least 10 events per year from rock-bottom minimal GZK predictions
Phase 1: look for right locationdeploy test strings in a few holes study attenuation, noise etc in-situ
The Salt ARENA I
IceCube Meeting Berkeley 11March, 23 2005
The Salt ARENA IAdd acoustic detector array to SalSA?
Theoretical expectations :
Water
Ice Salt
ρ [g/cm3]
1 .9 2.1
Vs [m/s] 1450 3800 4500
P/Pwater
1 10 25
f/fwater 1 ~3 ~6
eff. abs ~km 7 ? km
noise large small ?
small ?From B.Price at SLAC meeting 02/05
Need measurements :learn from geophysicists
f = 1 – 100 kHz, fres = 150 kHz
Signal attenuationλatt = 1/α
S = Ae-αr/rn
n = 2 usedλatt ≈ 170 m !
Signal location< 1 m
T. Spies, J. Eisenblätter, J.Manthei,Z. f. angewandte Geologie, H2, 2002, 30and references therein
1 crack seen by 12 detectorspressure waves + shear waves
IceCube Meeting Berkeley 12March, 23 2005
The Salt ARENA II
http://www.lofar.org
interferometer in frequency range of 10 - 200 MHzarray of 100 stations of 100 dipole antennasbaselines of 10 m to 400 km
All-Sky monitor: transient events
LOFAR
salt pillars
Zechstein salt
Detect UHE ’s using rock salt in Northern Europe (Groningen)Monitor UHE CR’s with LOFARDevelop:
radar techniques for salt domestechniques to install antennas in salt domes
LOFAR + ZESANAZuidwending
Onstwedde
Zuidwending
7,5 km
From A. M. van den Berg, SLAC meeting 02/05A. M. van den Berg, SLAC meeting 02/05
IceCube Meeting Berkeley 13March, 23 2005
The Ice ARENA
IceCube Collaboration:
Study a hybrid optical-radio-acoustic array
Idea behind: try to cross calibrate the detector,if discovery is made with one technique, confirmation with different technique necessary
IC++ :o radio +acoustic optical (IceCube) o+r+a (IceCube+)
example:0.5 km spacing1.5 km strings91 stringsVeff = 58 km3
λabs min Nch GZK (H+S) events/year
1 km 4 min 0.5
1km 4 max 1.5
6 km 4 min 18
6 km 4 max 54
acoustic array alone:
acoustic noise :
From J. Vandenbroucke,IceCube meeting Uppsala 10/04
IceCube Meeting Berkeley 14March, 23 2005
The Ice ARENA Radio antennas for ice available and tested (RICE)Acoustic glaciophones under development :
iron ball
glass ball
Calibration (until now only in water)reference hydrophone: Sensortech SQ03: -163.3±0.3 dB re 1V/μPa
Improvement
(S/N)ib = 50 (S/N)gb = 15
From S. Böser et al., to be published
Testrun at proton beam:
Etot = 5.6 PeV – 1.7 EeVE min (1m) 10 PeV
P min: ~10 mPa
IceCube Meeting Berkeley 15March, 23 2005
The Ice ARENA Ice properties for propagation of light measured (AMANDA)Ice properties for propagation of radio signals measured (RICE)Ice properties for propagation of sound waves still to be measured
urgent requirement: study ambient noise measure absorption length
test foreseen for season 05/06
x Proposal:
use 3 holesdiameter: ≥ 6” depth: 400 m7 sensors per holelarge variation of ice properties at the surface non-equal spacing7 transmitters per holeno possibility for transmitter allingment azimuthal symmetry
IceCube Meeting Berkeley 16March, 23 2005
Timescale and Competition
Project R&D time R&D funding Realization Problems
KM3Net + acoustic 2004-2008 ~1 Mio E > 2012 deployment, cost
AUGER + Radio 2004-2008 ??? > 2008 AUGER Nord
SalSA + (acoustic) 2005-2008 3-5 Mio $ > 2008 location, acoustic, cost
ZESANA + LOFAR 2005-2008 ??? > 2010 cost
IC++ opt./rad./acou.
2003-2007 0.1 Mio E > 2010 location,acoustic
A hybrid extension could make IceCube the pre-eminent neutrino telescope at all cosmic energies
But other projects near to take over
IceCube Meeting Berkeley 17March, 23 2005
International ARENA Workshop
May, 17 – 19 2005
DESY, Zeuthen, GERMANY
http://www-zeuthen.desy.de/arena
IceCube Meeting Berkeley 18March, 23 2005
Summary + ConclusionsFor the observation of the tiny neutrino fluxes above 1018 eV
Optical detection techniques seem to reach their limits
Radio detectors start to become sensitive
Acoustic detectors have a big revival but still need R&D
Further progress would profit from
Combination of different detection techniquesin one project
Dedicated experiments at large scales
Network of worldwide cooperation