ARENA Workshop, 17-19 May, 2005
First Activities in Acoustic Detection of
Particles in UPVM. Ardid, J. Ramis, V. Espinosa, J.A. Martínez-Mora,
F. Camarena, J. Alba, V. Sanchez-MorcilloDepartament de Física Aplicada, E.P.S. Gandia, Universitat Politècnica de València
ARENA Workshop, 17-19 May, 2005
Contents
• DISAO group– Experience in acoustic fields and connections with
neutrino detection
• First activities related to particle detection– Design of piezoelectric transducers – Characterization and calibration of hydrophones– Simulation of the propagation of the signal in the sea
• Conclusions and future
ARENA Workshop, 17-19 May, 2005
ULTRASOUNDS TRANSDUCTIONNon-destructive analysis (fruits, leakages) MaterialsPositioning Vibroacoustics, holographyBiomass in fisheries PiezoelectricsNeutrino detection Difussors, room acousticsThermoacoustic Model Quality of soundIntense beams Noise mapping
NON-LINEAR ACOUSTICS PSYCHOACOUSTICS
DISAO group14 researchers working in: (3 of them with Ph.D. in experimental particle physics)
ARENA Workshop, 17-19 May, 2005
DISAO group
Non-destructive analysis
Positioning
Thermoacoustic modelNEUTRINO DETECTION
Intense beams
Noise mapping
Quality of sound
Room acoustics
DiffusorsVibroacoustics
Materials
Piezoelectrics
14 researchers working in:
Biomass in fisheries
ULTRASOUNDS
TRANSDUCTION
NON-LINEAR ACOUSTICS
PSYCHOACOUSTICS
Holography
ARENA Workshop, 17-19 May, 2005
Connections with neutrino detection
• Transducers of ultrasoundsExample of application: Non-destructive analysis of fruits
200
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1,5 3,5 5,5 7,5 9,5
F (N)
V (m
V)
Serie1
Serie2
Serie3
Serie4
Serie5
ARENA Workshop, 17-19 May, 2005
Connections with neutrino detection
• Studies in the seaExample of application: study of biomass in fisheries
Echoes of fishes
Surface reference transducerEmission reference
Surface echoTime (ms)20 12 14 164
ARENA Workshop, 17-19 May, 2005
Connections with neutrino detection
• Non-linear acoustics
Self-organization of sound
22
2
pTTt
T
Tpipiapt
p
E()Intense beams Thermoacoustic resonator
Amplitude
Spectrum
Initial conditions
V
VBVGz
V 22
41
Self-trapped states of sound
ARENA Workshop, 17-19 May, 2005
Design of piezoelectrics transducers
• Software based on the localized constants method using the modified KLM model, R. Krimholtz et al., Electronic Letters 6 (1970)
Electric gateV1 I1
Backwards acoustic gate
F2 u2
Forward acoustic gate
F2 u2
R0
jX1C0
Z0 0/4 m Z0 0/4 m
1 :
ARENA Workshop, 17-19 May, 2005
Design of piezoelectrics transducers
• Simulation of the whole transducer (not only the piezoelectric)
Friendly interface
ARENA Workshop, 17-19 May, 2005
Design of piezoelectrics transducers
• Results
-3 -2 -1 0 1 2 3
x 10-5
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-4
-2
0
2
4
6
8x 10
-6 Respuesta a la excitac ión Eg(t)
Tiempo (t)
Eg(
t)
2.5 3 3.5 4 4.5 5 5.5 6
x 105
-1
-0.5
0
0.5
1Respuesta a la excitac ión Eg(f)
Frecuencia (f)E
g(f)
Input acoustic impedance
Emitting and Receiving Transfer Functions
Excitation Response in Time and Frequency
ARENA Workshop, 17-19 May, 2005
Design of piezoelectrics transducers
• Next steps:– Exhaustive comparison between simulation and experimental results
– Comparison of the results with finite element methods
– Include piezoelectrics with different geometries (not only discs/cylinders)
– Upgrade the model including more effects by using secondary circuits
– Use it, to design the best piezoelectrics sensors for acoustic detection of neutrinos
• Future: – Include the improved model in the simulation package for acoustic
detection of neutrinos
ARENA Workshop, 17-19 May, 2005
Characterization and calibration of hydrophones
0 2 4 6 8 10 12
x 104
-10
0
10
20
30
40
frequency (Hz)
inte
ns
ity
(d
B)
Rough calibration of a hydrophone
expected
Rough calibration
• The calibration of hydrophones in the lab is not an easy task:– There are reflections, diffraction, etc, which could affect well-known
methods of calibration like the reciprocity method.– We are working in designing a method for hydrophone calibration
ARENA Workshop, 17-19 May, 2005
Characterization and calibration of hydrophones
• MLS (Maximum Length Sequence) signal:– Pseudo-random signal, analogical version of digital sequence
consisting of values 1 and -1. – Periodic with the period T=2N - 1, where N is the "order of the
sequence", and has a flat frequency distribution.
– Circular autocorrelation provides a delta function MLS order 6
ARENA Workshop, 17-19 May, 2005
Characterization and calibration of hydrophones
0 2 4 6 8 10 12
x 104
-130
-120
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-100
-90
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-70
frequency (Hz)
Inte
ns
ity
dB
(a
. u
.)
Frequency response
0 2000 4000 6000 8000 10000 12000-0.2
0
0.2
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0.8
1
1.2
time (samples fs=250 kHz)
Inte
nsi
ty (
a.u
.)
Time Response (after deconvolution)
• Time and frequency response of the system (two hydrophones + tank) using the MLS signal– knowing the response of two elements, we could know the third one
ARENA Workshop, 17-19 May, 2005
Characterization and calibration of hydrophones
• Next steps:– Learn more about the different effects involved in acoustic
calibration of hydrophones– Study the calibration with different signals (short signals with few
pulses, white noise, continuous waves, sweep signal, MLS) – Improve the conditions of measurement and calibration of the lab:
building an anechoic tank– Design a trustful system of calibration in the lab– Look for a ‘good and simple’ “neutrino” signal for calibration
• Future: – Design and characterize different sensors for neutrino detection– Design a trustful system of calibration in neutrino detection sites
ARENA Workshop, 17-19 May, 2005
Simulation of the propagation of the signal in the sea
• Since recently we are using The Acoustic ToolBox, which includes four acoustic models:– BELLHOP: A beam/ray trace code
– KRAKEN: A normal mode code
– SCOOTER: A finite element FFP code
– SPARC: A time domain FFP code
• We show the application of this code to learn about the contribution of the sea surface noise to the deep-water noise in the Mediterranean Sea.
ARENA Workshop, 17-19 May, 2005
Simulation of the propagation of the signal in the sea
• BELLHOP: beam/ray tracing. The rays with small angles of emission are curved and do not reach the deep sea.
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0
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3500
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4500
5000
Range (km)
Dep
th (
m)
Ray tracing in the Mediterranean Sea
=2º
=6.7º
=11.4º
=16º
ARENA Workshop, 17-19 May, 2005
0 1 2 3 4
x 104
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Range (m)
Tra
ns
mis
sio
n L
os
s (
dB
)
Transmission Loss in deep Mediterranean Sea
Simulation of the propagation of the signal in the sea
• Transmission loss for the propagation of sound in the Mediterranean Sea for a source in the surface and measuring in the sea floor for different depths given by the normal mode code KRAKEN.
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Range (km)
Tra
nsm
issi
on L
oss
(dB
)
Transmission Loss in deep Mediterranean Sea
Depth of the sea (m)
2400
3400
4100
f = 1 kHz f = 15 kHz, no absorp. in water
Depth of the sea (m)
2400
4100
ARENA Workshop, 17-19 May, 2005
Simulation of the propagation of the signal in the sea
• Next steps:– Learn more about acoustical oceanography codes– Include some effects, which are not taken yet into consideration– Use the parameters of possible neutrino detector sites (if available)– Compare the results with other simulation packages and validate them– Upgrade the model for acoustic neutrino detection purposes.
• Future: – Include the improved model in the simulation package for acoustic
detection of neutrinos– Use it for the inverse problem, neutrino source location
ARENA Workshop, 17-19 May, 2005
Conclusions and Future
• Conclusions:– We have started to work in some aspects of acoustic neutrino
detection: design of piezoelectric transducers, calibration of hydrophones and propagation of acoustic signal in the sea, reaching some results but knowing that there is a long way still.
– We have seen that we can apply knowledge from different acoustic fields to the neutrino detection problem
– Therefore, multidisciplinary collaboration of acoustic and particle physics people is encouraged
• Future: – To consolidate this line of research in our group– To participate in an international collaboration which faces this
complex problem in an organised and efficient way.