Cosmic Ray Test of INO RPC StackM. Bhuyan1, V.M. Datar2, S.D. Kalmani1, S.M. Lahamge1, N.K. Mondal1,

P. Nagaraj1, S. Pal1, L.V. Reddy, A. Redij1, D. Samuel1, M.N. Saraf1, B. Satyanarayana1, R.R. Shinde1 and P. Verma1

 

India-based Neutrino Observatory (INO) Collaboration

1Department of High Energy Physics, Tata Institute of Fundamental Research, Mumbai 400005, India

2Nuclear Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India

Plan of my talk

• Introduction to INO RPC system.• Early results.• Construction of 1m X 1m RPCs.• Cosmic ray test stand and the DAQ system.• RPC performance studies using cosmic muons.• Monitoring long term stability of INO RPCs.• Future outlook and summary.

INO RPC system

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INO Detector – Channel CountNo of modules 3

Module dimension 16 m X 16 m X 12 m

Detector dimension 48 m X 16 m X 12 m

No of layers 140

Iron plate thickness 6 cm

Gap for RPC trays 2.5 cm

Magnetic field 1.5 Tesla

RPC unit dimension 2 m X 2 m

Readout strip width 2 cm

No. of RPCs/Road/Layer 8

No. of Roads/Layer/Module 8

No. of RPC units/Layer 192

Total no of RPC units 27000

No of Electronic channels 3.6 X 106

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Cosmic Muon Test using small RPCs

Stack of 10 RPCs

Gas unit

Telescope

DAQ

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Early results

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RPC building blocks

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Fabrication of 1m x 1m RPCs

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INO 1m X 1m RPC Stack

Constructional details of the gas system

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F ron

t vie

w

Inte

rnal

vie

w

Rear

vie

w

VME BASED DAQ SETUPX strip data

Y strip data

Timing info

DigitalFront End

AnalogFront End

TriggerModule

Event Trigger

Event/Monitor Data

VME CRATE Scaler TDC

Readout Module

Linux based DAQ software (C++, Qt, ROOT)Interrupt BasedMulti-ThreadedGraphical User Interface

Online 2D/3D Event DisplayRPC Strip MonitoringOnline Error Reporting

RPC Stack

Poster by Deepak Samual for more details about INO DAQ

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Design and implementation of the data acquisition system

200 boards of 13 types

Custom designed using

FPGA,CPLD,HMC,FIFO,SMD

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Some interesting cosmic ray tracks

Track Reconstruction

Zenith Angle distribution of cosmic ray tracks 2c distribution of fitted tracks

Study of RPC performance using cosmic rays

Strip Multiplicity due to crossing muons Track residue in mm

Image of a RPC using muons

RPC efficiency

RPC timing study

Poster by S. Pal for more details on timing studies

Particle direction using time information

Velocity ( ) b distribution ( linear) Velocity ( b ) distribution (log)

Average layer-wise time plot for muon tracks in the RPC stack.

Long term monitoring of RPC currents

Monitoring of strip counting rate

Summary

• We have successfully built and operated Glass RPCS in avalanche mode.

• A stack of 12 such RPCs being used continuously to monitor their performances using cosmic muons.

• Currents and noise rates are being monitored over long periods. No degradation after 2.5 years of operation.

• The setup will be used for further studies and as a test stand to test new frontend electronics & DAQ.