Acoustic activities around Marseille

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Acoustic activitiesaround Marseille the
ANTARES site

• Vincent BERTIN - Michel BILLAULT - Pascale KELLER
  - Auguste LE VAN SUU - Valentin NIESS
• Centre de Physique des Particules de Marseille /
  ANTARES

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The ANTARES detector
to be deployed by 2004-2006

• 900 PMTs
• 12 lines
• 25 storeys / line
• 3 PMTs / storey

Submarine links
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The ANTARES site
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The ANTARES collaboration
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ANTARES achievements and planning
Jun 00 implosion test
1996 1997 1998 1999 2000
_________________
2001 2002 2003 2004 2005 2006
May 03 Jul 03 MIL PSL
recovered
Dec 02 Pre-production Sector Line (PSL) deployed
Dec 02 Junction Box deployed
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Pre-production Line ready Nov 2002
Intensively tested and calibrated in laboratory
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Deployment Pre-production Line Dec 2002
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The Mini Instrumentation Line
MIL hosts instruments for environmental
measurements and devices for detection line
calibration (acoustic system, light beacons)
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Submarine cable connection
Performed with Nautile in March 2003
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Layout of ANTARES site
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Sensitivity to point-like sources
90 c.l. Muon flux limits (cm-2 s-1)

• ANTARES has 3.6p sr coverage
• Complementary to AMANDA/IceCube with 1.6p sr
  total overlap
• Galactic centre seen 70 of the time
• High sensitivity due to good angular resolution
  (0.2-0.3 for En gt10 TeV)

E-2 n spectrum
After 1 year, Antares can improve limit for
Southern hemisphere or discover something !
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RD on acoustic detection in Marseille
Large uncertainty on acoustic noise level at high
depth

• In situ measurement necessary to estimate
  feasibility of acoustic detection long term
  recording as function of frequency, surface noise
  (trafic, wind sea conditions,)use Antares
  infrastructure CEM Trémail deep array
• Search for deep sea hydrophones with high
  sensitivity and low intrisic noise
• Develop acquisition system for hydrophones
  stand-alone measurements and interfaced on
  Antares instrumentation string (permanent DAQ
  with direct link via optical fibre)
• Simulation studies of neutrino acoustic signal
  properties, of detector geometry, reconstruction
  algorithms,

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Acoustic skills around Toulon

• Toulon is the military base of French Navy in
  Mediterranean Sea Lots of specialised
  industry in various marine activities like
  underwater acoustic
• We benefit from local competence of
• IFREMER - Toulon Institut Français de Recherche
  sur la Mer
• CEM Ile du Levant Centre dEssai de la
  Méditerranée (French Navy tracking array)
• CESN St Jean Cap Ferrat French navy
  hydrophone array to study submarine noise
• Thales / PONS Aubagne constructor of
  hydrophones and acoustic antennas
• Genisea / ECA / Osean Toulon industry
  speciallised in acoustic and underwater
  electronic systems
• Thetis / Ixsea Oceano Carqueirranne industry
  specialised in acoustic positioning systems and
  water current measurements
• Semantic Sanary industry specialised in
  theoritical computation in acoustics, signal
  analysis and filtering algorithms

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ANTARES Acoustic positioning system

• High Frequency (40-60 kHz) Long BaseLine
  acoustic system allowing the precise relative
  positioning of the ANTARES detector OMs by
  acoustic triangulation of hydrophones installed
  along each string (precision lt 10 cm)

Electronics(Emission/Reception/Detection)
Transducer(Emission/Reception)
Soundvelocimeter
Sound velocimeter CTD probes
Pressure sensor
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Acoustic positioning prototype
4 transponders
Y coord. Range 3 (m)
Triangulation ? 5 cm final precision
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TREMAIL French navy tracking array
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TREMAIL location
40 km submarine cable
-2475m
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TREMAIL acquisition system

• Data taking campaign in June 2001
• 8 hydrophones _at_ 1500 and 2500 m
• sampling frequencies 250 kHz
• filters window 100-100 kHz
• 3Gbytes of data

Landing cables
Hydrophones polygone TGF
Pré amplis
Control room of TREMAIL proprietary DAQ system
PC DAQ CHICO Boards Convertisseurs AIX 4 or 8
channels 16 bits 2MSamples/sec HD SCSI UW
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Preliminary result on TREMAIL site
Noise measurement averaged on 150s recording
sea conditions with 25-30 knots speed
Acoustic pinger _at_ 4.5 kHz
H14 _at_ 1430 m
H21 _at_ 2430 m
Lots of uncertainty on gain, sensitivity, of
acquisition chain to be redone (soon ?)
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Hydrophones Market Survey
Hydrophone Manu-facturer Sensitivity (dB ref 1V/µPa) Resonance (kHz) Equivalent Noise (dB ref 1µPa/Hz1/2) Survival Depth (km)
SQ03 Sensor Tech. Ltd -202 65 29 6.5
G-207404 Genisea -200 60 23 2 6.0
G-176407 Genisea -193 60 22 2 6.0
TC-4042c01 Reson -193 65 20 2.5
TC-4037 Reson -193 65 20 2.0
Tuba 6000 Thales/Pons -193 ? ? 6.0
ITEP ITEP -180 50 (?) 4 2 4.0
DS-628 Ing. Acoustic Inc. -180 ? ? 20- 3.0
ANTARES Positioning
SS-0 20 dB Ref 1µPa/Hz1/2
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Our choice The ITEP Hydrophone !
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Sensitivity of ITEP hydrophones
-152 dB ref V/µPa
Including 28 dB pre-Amp
Noise Power N 4 kB T R Natural piezo
Noise N ? R ? Gain
10 kHz
50 kHz
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Directivity of ITEP hydrophones
j angle
_at_ 16 kHz
_at_ 40 kHz
q angle
Natural damping of surface noise
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Measurement of ITEP hydrophone self-noise

• Electric self noise spectrum measured by
  substraction Noise adds quadratically while
  correlated induced noise substracts itself
• Calibration of setup gain by using a 100 O
  (0.1) No thermal drift resistor
• Setup self noise measured by a short-cut (1 W
  resistor)

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Measurement of ITEP hydrophone self-noise
100 W resistor
Amp/pre-Amp noise ?
Calibration white noise
-150 dB ref 1V/Hz1/2
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Acoustic measurements in IFREMER Pool
BrüelKjær 8100
ITEP hydro
receivers
emitter
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Acoustic measurements in IFREMER Pool
1 ms
10 dB
To add
Shape of the signal received on ITEP hydro
Mean level -150 dB ref 1V/mPa but large
uncertainties ?5 dB due to local reflections
between receivers
Sensitivity measurements
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Ambiant noise in IFREMER Pool
25 dB ref 1mPa/Hz1/2 _at_ 40-50 kHz Sea state 1/2
To add
-125 dB Ref 1V/Hz1/2
40 kHz
50 kHz
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Acoustic measurement acquisition system
Autonomous acquisition system to characterize the
ambient noise of the ANTARES site and to
evaluate the feasibility of acoustic detection.
Schematic
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Specifications of acoustic acquisition system

• Hydrophones 4 typically (min. 3 max. 6)
• Filtering bandwidth 10 kHz - 100 kHz
• Sampling 16 bits _at_ 500 kHz / hydrophone
• Automatic amplification gain control
• Signal processing facilities - event selection
  filter - (DSP)
• Very low level electronic noise
• Either autonomous in energy and data storage or
  interfaced on ANTARES line electronics
• Data acquisition of the sound velocimeter and
  tiltmeter-compass
• Acoustic modem link to have interface with
  surface boat (remote control)