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Summary of the Acoustic R&D Parallel Session
R. NahnhauerDESY
September 23rd, 2011 IceCube Meeting Uppsala 1
x
AAL
Quo vadis?
IceCube Meeting Uppsala 2September 23rd, 2011
IceCube Meeting Uppsala 3September 23rd, 2011
x
IceCube Meeting Uppsala 4September 23rd, 2011
Four journal publications:
Y. Abdou et al., arXiv: 1105.4339 , subm. to NIMA technical paperR. Abbasi et al., APP 33(2010)277 speed of soundR. Abbasi et al., APP 34(2011)382 att. lengthR. Abbasi et al.,arXiv:1103.1216, subm. to APP noise&transients
Five PhD Thesis
Several Bachelor, Master, Diploma Thesis
A lot of data could still be evaluated: inclined speed of sound noise sources shadowing effects frequency behaviour etc., ect.
Mission (nearly) accomplished !
IceCube Meeting Uppsala 5September 23rd, 2011
Sensor noise behavior stable over years:Compare 20092011
IceCube Meeting Uppsala 6September 23rd, 2011
IceCube Meeting Uppsala 7September 23rd, 2011
Aim: learn more about detector efficiency vs. and learn more about noise sources (get hits in both channels of one sensor nearly only from acoustic signals, i.e. from reconstructed events - hint that measured noise level is caused by sensor electronics)
Distance: 10 cm
IceCube Meeting Uppsala 8September 23rd, 2011
Similar behavior found for later measurement with string D sensor
IceCube Meeting Uppsala 9September 23rd, 2011
AachenAcousticLaboratory
IceCube Meeting Uppsala 10September 23rd, 2011
Perform reciprocity calibration for AAL transmitters Do for SPATS3- reciprocity cal.- hybrid cal. (use calibrated transmitter)
Check result of early 2011
IceCube Meeting Uppsala 11September 23rd, 2011
increase systematical error
IceCube Meeting Uppsala 12September 23rd, 2011
13Uppsala 21.09.2011 IceCube Collaboration meeting
A one layer PVDF acoustic sensor. Thermoacoustic effect in water
Oservations:Clean bipolar signal (thermoacoustics signal)Polarity inversion of the thermoacoustics signal at around 4 °C
Sascha Cramer Bachelor thesis
Sasc
ha C
ram
er
IceCube Meeting Uppsala 14September 23rd, 2011
IceCube Meeting Uppsala 15September 23rd, 2011
water South Pole ice salt
= c2k/CP 0.153 1.12 2.87
fmax (kHz) 7.7 20 42
signal strength ~ Gruneisen parameter
First reliable direct comparison of signal strength in water and ice !
Measurement confirms expectations for
Speed of sound Frequency Signal strength
Final calibration stillnecessary
IceCube Meeting Uppsala 16September 23rd, 2011
Venio Romam iterum
crucifigi. Quo vadis, Domine?
Quo vadis?
From problems to success
IceCube Meeting Uppsala 17September 23rd, 2011
J. Berdermann1), M. Carson2), R. Nahnhauer1) 1)DESY, 2)Gent University
How a hybrid radio-acoustic detector in ice could look like
Aim of the new simulation study
Check the general possibilities of a hybrid detector concept for a x*100 km3 cosmogenic neutrino detector Discuss some of the basic requirements for a necessary R&D program, as there are e.g.
- new (robotic) drilling and deployment technologies - new power and communication systems - new type of cable integrated sensors - new data collection, reduction and transfer concepts - etc. pp
It is NOT the aim of this study to work out a concept which tomorrow can be started to be build – the realistic timescale is at least of O(10years)
A 2-3 orders of magnitude larger detector than ever built can not just be a blow-up of an older one but needs new ideas and techniques
IceCube Meeting Uppsala 18September 21st, 2011
The next radio detector at the Pole - ARA
37 clusters nearly without correlations per eventNo hybrid (acoustic) optionforeseen and possible holes too distant (1.3-2 km) holes not deep enough
148 holes
IceCube Meeting Uppsala 19September 23rd, 2011
Don’t give up the hybrid idea for UHE neutrino detection
still important because of :- Signal Identification
- Noise Reduction
- Detector Calibration
- Event Reconstruction
- Energy and Direction Resolution
Acoustic technology may do for low cost at least part of the job, as long as better alternatives are missing
Do now necessary simulations based onreasonable measurements
Maryland 2009 Workshop
IceCube Meeting Uppsala 20September 21st, 2011
Comparison with radio triggers II (model dep.)
coinc. events/year (ESS-2008)Learned Askaryan Dedenko
0.6 (6) 1.8 (18) 2.7 (27)
e 0.3 (3) 0.9 (9) 1.3 (13)
all 0.9 (9) 2.7 (27) 4.0 (40)
coinc. events/year (ESS-2008)Learned Askaryan Dedenko
2.1 (21) 5.0 (50) 6.3 (63)
e 1.0 (10) 2.4 (24) 3.0 (30)
all 3.1 (31) 7.4 (74) 9.3 (93)
10 mPa 1 mPa
6%11%
16% 35%
29%
18%
IceCube Meeting Uppsala 21September 21st, 2011
ConclusionsFor considered grid arrays in average about 10% of radio events have additional acoustic signal - ~80% of those give own acoustic trigger
depth dependence: 200-400 m would be okthe deeper the better (200-1000m gives factor 2)
threshold dependence10 mPa would be okthe lower the better, particularly for lower energies
grid constant dependence500 m spacing would be ok333m spacing better, particularly for lower energies
In general:
reasonable number of coincident events detectable only withlarge scale detector (~400 km2)
IceCube Meeting Uppsala 22September 23rd, 2011
IceCube Meeting Uppsala 23September 23rd, 2011
IceCube Meeting Uppsala 24September 23rd, 2011
IceCube Meeting Uppsala 25September 23rd, 2011
Ultima hora latet