Experiences with RPC Detectors in Iran and their Potential Applications Tarbiat Modares University Ahmad Moshaii A. Moshaii, IPM international school and workshop on Particle Physics (IPP12) IPM international school and workshop on Particle Physics (IPP12): Neutrino Physics and Astrophysics School of Physics, IPM, Tehran, Iran September 26-October 1, 2012 (5-10 Mehr, 1391) (TMU)Tarbiat Modares University, Tehran, Iran
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Experiences with RPC Detectors in Iran and their Potential Applications
IPM international school and workshop on Particle Physics (IPP12): Neutrino Physics and Astrophysics School of Physics, IPM, Tehran, Iran September 26-October 1, 2012 (5-10 Mehr , 1391 ). Tarbiat Modares University. Experiences with RPC Detectors in Iran and their Potential Applications. - PowerPoint PPT Presentation
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Experiences with RPC Detectors in Iran and their Potential Applications
Tarbiat Modares University
Ahmad Moshaii
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
IPM international school and workshop on Particle Physics (IPP12): Neutrino
Physics and AstrophysicsSchool of Physics, IPM, Tehran, Iran
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
electric field
electric field
electric field
extEA. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
RPC Operation Regions
I
I. RecombinationII. IonizationIII. ProportionalIV. Limited ProportionalV. Geiger-MullerVI. Discharge
II III IV V VIV1 V3V2 V5V4 V6
Applied Voltage
Puls
e Am
plitu
de (l
og sc
ale)
Modes of Operation
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
RPC Streamer Mode
RPC Avalanche Mode
Breakdown Point
I
I. RecombinationII. IonizationIII. ProportionalIV. Limited ProportionalV. Geiger-MullerVI. Discharge
II III IV V VIV1 V3V2 V5V4 V6
Applied Voltage
Puls
e Am
plitu
de (l
og sc
ale)
Modes of Operation
A. Moshaii, First IPM Meeting on LHC Physics, Isfahan 20-24 April, 2009
Space Charge Becomes Important
I
I. RecombinationII. IonizationIII. ProportionalIV. Limited ProportionalV. Geiger-MullerVI. Discharge
II III IV V VIV1 V3V2 V5V4 V6
Applied Voltage
Puls
e Am
plitu
de (l
og sc
ale)
Modes of Operation
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
Space Charge Effect:
The electrons are collected relatively quickly (ns) at the anode leaving behind the positive ions that move much more slowly. The positive ions form a space charge that appreciably distort the electric field and the process of electron avalanche inside the gap.
Modes of Operation
Space charge is the main factor restricting the avalanche growth
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
Simulation of RPC performance
Based on Transport Equations:
Stxntxntxnxt
txneee
e
),(),(),(
),(
Stxnttxn
e
),(),(
Stxnttxn
e
),(),(
ne is the number density of electrons
n+ and n- are the number densities of positive and negative ions
S is photon contribution for the electrons avalanche
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
Simulation Input:
MAGBOLTZ (Townsend Coefficient, Attachment Coefficient, Drift Velocity) Steve Biagi
Dynamic Simulation
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
Dynamic Simulation
Space Charge:
xd
AnodeCathode
x
R
x
d
xPREd
xEd
Origin
r
xdRxx
xxEIm
xxdiscx
2201 12
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
r
Gap
AnodeCathode
P
Dynamic Simulation
Space Charge:
d
d
d
x
x
dtotx IIIIEE
2
110
1
0
1chargeSpace
x
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
= Initial condition= Boundary condition = Interior point
Finite Difference Method (Lax Numerical Scheme):
Time
Distance
Dynamic Simulation
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
Dynamic Simulation
1) Avalanche Mode
2) Avalanche to Streamer Transition
3) Streamer Mode
R. Cardarelli, V. Makeev, R. Santonico,Nucl. Instr. and Meth. A382 (1996) 470
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
Dynamic Simulation
Initial Conditions:
1) Avalanche Mode
sStepsTime
kVHVSFHCiHFC
10
6104242
101
103.0/3/7.96//
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
Monte Carlo Simulation & Results
Charge Spectrum:
3.0/3/7.96// 6104242 SFHCiHFC
Dynamic Simulation
Spatiotemporal Growth:
1) Avalanche Mode
approximate analytical solution.
Compared to:
P. Fonte, IEEE Trans. Nucl. Science, 43:2135–2140, 1996
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
Dynamic Simulation
1) Avalanche Mode
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
Dynamic Simulation
Space Charge Field:
1) Avalanche Mode
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
Dynamic Simulation
1) Avalanche Mode (5 Clusters)
Initial Conditions:
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
Dynamic Simulation
1) Avalanche Mode (5 Clusters)
Spatiotemporal Growth:
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
Dynamic Simulation
1) Avalanche Mode (5 Clusters)
Spatiotemporal Growth:
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
Dynamic Simulation
1) Avalanche Mode (5 Clusters)
Spatiotemporal Growth:
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
Dynamic Simulation
1) Avalanche Mode (5 Clusters)
Spatiotemporal Growth:
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
1) Avalanche Mode (5 Clusters)
Spatiotemporal Growth:
Dynamic Simulation
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
1) Avalanche Mode (5 Clusters)
Total Electric Field:
Dynamic Simulation
Still not enough to distort the applied field
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
1) Avalanche Mode (5 Clusters)
Dynamic Simulation
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
2) Avalanche to Streamer Transition
Dynamic Simulation
sStepsTime
kVHVSFHCiHFC
10
6104242
101
04.113.0/3/7.96//
Spatiotemporal Growth:
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
2) Avalanche to Streamer Transition
Dynamic Simulation
Space Charge Field:Space Charge is becoming
comparable to the applied field
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
3) Streamer Mode
Dynamic Simulation
Spatiotemporal Growth:
sStepsTime
kVHVSFHCiHFC
10
6104242
101
42.113.0/3/7.96//
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
Dynamic Simulation
3) Streamer Mode
Pre-Pulse
Streamer Pulse
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
Main Simulation outputs:
Monte Carlo Avalanche Simulation
Space Charge
Avalanche Mode
Saturated Avalanche Mode
Streamer Formation
Dynamic Simulation
A. Moshaii, IPM international school and workshop on Particle Physics (IPP12)
Window glass HIGH RESISTIVITY ELECTRODE
Window glass
Experimental activities with RPC detector
GAS GAP
Silicone glue
38 cm45 cm
GRAPHITE COATING
Graphite coating
20 kΩ
HV connection
INSULATOR
Mylar sheet
READOUT STRIPS X
READOUT STRIPS Y
Resistor R=50 ΩFaraday
cage
Aluminum foil
Gas Mixing System Diagram
Construction of the Gas Mixing System for RPCs
150
cm
50 cmConstruction of the Gas Mixing System for RPCs
2- States Valve: To allow the gas flow
Regulator: To adjust the input gas pressure
Pressure Gauge: to show the input gas pressureTemperature Gauge: to show the input gas temperatureMixer: to mix the used gases (Ar/CO2)Low Range Flow Meter( 0-20 L/H)3-States valve: To select the output gas mixtureGas Mixture OutputsBubbler: To have a uniform flow in RPCPressure Gauge: to show the mixed gas pressure
Gas Connector
Glass RPC
HV Supply
ground
+HV
-HV
Digital oscilloscop
e
signal
Gas inputGas output
Gas mixin
g syste
mAr
50 Ω
CO2bubbler
Experimental Setup
Experimental Study of the RPCs Time Resolution
1/16/2010TMU44
Glass RPC
HV Supply
ground
+HV
-HV
Digital oscilloscop
e
signal
Gas inputGas output
Gas mixin
g syste
mAr
50 Ω
CO2bubbler
Charged particles
Rise Time: Electron Component Fall Time: Ion Component