Transcript Diapositiva 1

International ARENA Workshop
May 17-19, 2005
DESY, Zeuthen
Giulia De Bonis
University “La Sapienza”
Rome, ITALY
Preliminary Results on
Hydrophones Energy
Calibration
with a Proton Beam
Results at an intense low-energy proton beam in
ITEP (Moscow),
special thanks to Vladimir Lyashuk and Andrei Rostovstev group
• Nprotons ~ 1010
• Eprotons = 100 MeV, 200 MeV
Overview
• Hydrophones Characterization
(Frequency Response)
• Hydrophones Calibration on Proton Beam
• Future Developments
Piezo-Electric HYDROPHONES
RESON 4042
(modified)
BENTHOS
(prototipe)
previously used for 6
months at 2000 m depth.
L = 15.5 cm
d = 2 cm
Both hydrophones are pre-amplified (~ 30 dB)
Frequency Response -
the Hydrophones Sensitivity
Test at IDAC (CNR – Roma)
Data Analysis Results
CALIBRATION - Frequency Response
IDAC – Institute of Acoustics “O. M. Corbino” – Rome (Italy)
http://www.idac.rm.cnr.it/
 UAL - Underwater Acoustics Laboratory
water tank (fresh water)
remotely-operated
transducer positioning system
capable of handling weights up to 100 kg
on two independent carriages
with dimensions:
6.0 m (length
4.0 m (width)
5.5 m (depth)
Experimental Set-Up
Hydrophone
Spherical Transducer
(Model ITC 1007)
The signal source (Reson ACS 9060) produces
a 5KHz to 25 KHz sine wave (frequency sweep
with a step of 0.5 KHz).
1.5 ms
L=2.8 m
(depth)
d=1 m
(distance)
CALIBRATION - Frequency Response
RESULTS
RESON - Calibrazione
BENTHOS - Calibrazione
-173 dB re 1V/1mPa
-172.0
-180
-183 dB re 1V/1mPa
-181
-172.5
A [ dB re 1V/ uPa ]
A [ dB re 1V/ uPa ]
-182
-173.0
-173.5
-174.0
-183
-184
-185
-186
-174.5
-187
-175.0
-188
5000
10000
15000
20000
25000
5000
10000
15000
Frequenza [ Hz ]
Frequenza [ Hz ]
Benthos
Reson
20000
Hydrophones sensitivity is measured in dB re 1V/1mPa
25000
Protons Interaction in Water -
the Acoustic Signal
Nprotons/spill ~ 1010
Eprotons = 100 MeV, 200 MeV
up to 1018 eV deposited per spill
-Test at ITEP (Moscow) Proton beam
- Preliminary Data Analysis Results
Particles Interaction in Water:
the Acoustic Signal
“ instantaneous ”
& localized
energy deposition
local heating of
the medium
Local density variation
PRESSURE WAVE
The Bragg Peak
If the proton energy is in the range 100-200 MeV, the most
of the primary proton energy is deposited at the Bragg Peak.
The Bragg Peak is a good approximation of a localized highdensity energy deposition in water.
Considering the Bragg Peak one can simulate an acoustic
source.
ITEP Experimental Set-up
June 2004
Dimensions
50.8 cm × 52.3 cm × 94.5 cm
Transducer
Positioning
System
The 90% of the basin's volume is filled
with fresh water. NO control on
temperature.
Beam
Output
V.Lyashuk and A.Rostovstev group,
G. De Bonis, G. Riccobene, R. Masullo
and A. Capone
Data Acquisition
BENTHOS
with 3 different hydrophones
B
T
ITEP
R
RESON
Injection
Tube
Beam
Output
Collimator
p
B  -173 dB re 1V/1mPa
R  -183 dB re 1V/1mPa
T  -133 dB re 1V/1mPa
Hydrophones Configuration
RESON
Z [ cm ]
BENTHOS
p
ITEP
BENTHOS
RESON
X [ cm ]
(Monte Carlo Simulation)
TTX Data
BENTHOS
RESON
ITEP
BCT
Beam
Current
Transformer
Hydrophones
Hydrophones Data - a Zoom View
Electro-magnetic
induced pulse
Typical pulse collected
with 1010 protons @ 200 MeV
A ~ 45 mV
 ~ 50 ms
Acoustic Pulse
related to protons interaction
Bipolar Shape
Hydrophones Data Analysis
FIT Operation
y  y0  AMAX 
( x  P1 )

e
  ( x P ) 2 
2
 
 
  2  


BENTHOS
y  y0  AMAX  e
RESON
ITEP
 1  ( x  P ) 2 
1
 
 
2 
 

Bipolar Amplitude
Results - LINEARITY
Proton Intensity
Ebeam = 100 MeV
BENTHOS Hydrophone
Total deposited energy = 108 [eV]• 2. 5·1010 =2.5 ·1018 eV
Nprotons= 2. 5·1010
Ebeam = 200 MeV
Linear
Fit
Results - LINEARITY
RESON Hydrophone
E = 100 MeV
E = 200 MeV
Linear
Fit
Results - LINEARITY
ITEP Hydrophone
E = 100 MeV
E = 200 MeV
Linear
Fit
Collimator Diameter Dependance
The BCT gives a measure
of the number of protons
BEFORE the collimator
Results show a collimator
diameter dependance
0
0.5·1010
1.0·1010 1.5·1010
2.0·1010 2.5·1010
Beam Intensity [Nprotons]
BENTHOS Data – E=100 MeV
Number of entering protons
The voltage signal measured at the BCT channel is proportional to the
number of protons in the emitted bunch.
One can calculate Nproton using the formula:
Nproton = ABCT [ V ] · 2 · C ·108
where C is a parameter depending on machine settings;
the C-value is given by machine technicians.
More over, collimators, located downstream the BCT, are used to
modify the number of protons interacting in water.
We considered collimator with diameter f = 2, 3, 5 cm).
Results
(taking into accounts the effect of collimators…)
Ebeam= 100 MeV
0
0.5·1010
1.0·1010
1.5·1010
2.0·1010
Nprotons ENTERING THE BASIN
2.5·1010
Future Plans
• Simulation (Geant4) of proton beam
energy deposition in water
• Simulation of acoustic signal formation
• Development of a tool for open sea
hydrophone calibration (controlled
sparker)
• Simulation of acoustic signal from UHE
neutrino induced showers in sea water