Transcript Slide 1

ARNAB BANERJEE
Variable Energy Cyclotron Centre, India
VECC participation
a. Build ~10% of the MRPC modules (~12 + spares)
b. Will provide hardware for the entire low voltage system
c. Take part in data analysis, calibration, simulation
RPC/MRPC building experience at VECC
1. Facilities developed for RPC R&D for India-based Neutrino
Observatory (INO):
Oscillation of atmospheric neutrinos

L’
q
L ~ 10 km for down going 
~12000 km for up going 
 E~ few MeV-100GeV
Down  near detectorno oscillation
Up  far detector  Oscillation
L
q
N up(L/E)
= P(m  m; L/E)
N down(L’/E)
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INO Detector
Iron Calorimeter (ICAL)
Magnetic field ~ 1 Tesla
along y-direction
Mass: 50 kTon
Size : 48 m (x) 16m (y) 12 m (z)
140 layers of 6 cm thick iron
with 2.5 cm gap for active elements
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Resistive Plate Chamber for INO
Two 2 mm thick float Bakelite
Separated by 2 mm spacer
2 mm thick spacer
Pickup strips
Resistive plates
Complete RPC
Graphite coating on the outer surfaces of Resistive plates
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Full facility for testing 12RPCs simultaneously and
forming tracks in mag. Field
8 Glass RPC + 4 Bakelite RPC
1 Tesla Uniform magnetic
field
1m x 1m Bakelite
RPC build at VECC
 gas system
 HV
 LV
 FEE
2. Double Gap Bakelite MRPC:
Bakelite: procured locally.
Dimension: 30 cm X 20 cm
3. Four Gap Bakelite MRPC:
Dimension: 23 cm X 23 cm
Grooving for gas Perspex
flow (4 mm X 2 base
mm)
10 mm
230 mm
230 mm
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4. Six Gap Glass RPC:
Dimension : 20 cm X 8 cm
Glass: procured from GSI
Glass Thickness: 600 μm
Gas gap: 200 μm
 Graphite paint is used
as conductive material
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cosmic-ray
test setup
Gas distribution system (MFC based)
Gas: Ar, iso-butane, SF6 ,
Freon(R134a)
Can be adjusted for both streamer &
avalanche mode
Schematic representation of cosmic ray setup
Master trigger signal = SC1 .AND. SC2 .AND. SCF
Efficiency = (RPC count in coincidence with master trigger)
(Master trigger count)
Time resolution : START with Master trigger
STOP with MRPC
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1m X 1m Bakelite RPC
8
80
60
6
60
40
20
0
6
70
FWHM
FWHM (ns)
Efficiency (%)
100
50
4
40
2
30
average arrival time
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8
9
High Voltage (kV)
10
0
7.5
8.0
8.5
High Voltage (kV)
9.0
average arrival time (ns)
1.
Efficiency > 90%
Time resolution (FWHM) ~ 3 ns
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2.
Bakelite MRPC
Efficiency > 95%
Time resolution(FWHM) ~ 2 ns
3.
Glass MRPC
Efficiency > 90%
Time resolution ~ 500 ps (σ)
Facility at VECC for LMRPC production for MTD:
• New Lab for LMRPC production
• Gas distribution system
• HV
• Cosmic setup
Requirements from the collaboration:
 Read-out system ( electronics for high time resolution measurement)
 Raw materials (glass, fishing line , scintillators, etc.)
 Pick-up strips
 Painting materials & procedure
Are they centrally available ???
Production Plan:
After having all the raw materials
Fabrication :
Module
Time
1
~ 20 days
12
~ 1 years
After having all the Read-out system
Testing :
Module
Time
12
~ 1.5 years
If required we can do both the fabrication and test simultaneously
Analysis:
Analysis is going on for : RUN10 : Cosmic
RUN9 : p-p collision
Plots for RUN10 cosmic:
plots indicates the position
of the MTD properly