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Presentation on the proposed detector and data readout system for the India-based Neutrino Observatory, focusing on RPC basics, electronics, and research results.
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Proposed detector and data readout system for theIndia-based Neutrino Observatory(INO) B.Satyanarayana(For INO collaboration)Department of High Energy PhysicsTata Institute of Fundamental ResearchHomi Bhabha Road, Colaba, Mumbai, 400 005E-mail: bsn@tifr.res.in
Plan of the talk • Introduction • Proposed detector • RPC basics • RPC test stand • Gas mixing and distribution system • RPC R & D results • Electronics for the prototype detector; • Thoughts for the final detector • Status and future plan NSNI-2004, Kalpakkam, February 17-20, 2004
What and Why Neutrinos? • Neutrinos are one of the fundamental particles of matter. • Electrically neutral and were initially thought to be mass-less. • Three types or flavors of neutrinos known. • Recent evidence indicates that neutrinos have mass and also experience mixing among these flavors. • Neutrino oscillations can explain the discrepancy between theory and observations about its flux. • Neutrino mass can also be indirectly estimated by detecting its eventual oscillations. • Non-zero mass for neutrino has profound implications on fields as varied as nuclear physics, particle physics, astrophysics and cosmology. • Pioneering experiments at the KGF underground laboratories NSNI-2004, Kalpakkam, February 17-20, 2004
INO Collaboration B.S.Acharya, Sudeshna Banerjee, P.N.Bhat, S.R.Dugad, P.Ghosh, K.S.Gothe, S.K.Gupta, S.D.Kalmani, N. Krishnan, N. K Mondal, B.K.Nagesh , P.Nagaraj, Biswajit Paul, A.K.Ray, Probir Roy, B.Satyanarayana, S.Upadhaya, P.Verma Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai V.M.Datar, M.S.Bhatia, S.K.Kataria Bhabha Atomic Research Centre, Mumbai P. Bhattacharya, S.Bhattacharya, S. Chattopadhyay, A.Ghoshal, A.Goswami K. Kar, D.Majumdar, P.B.Pal, S. Saha, M. Sharan, S.Sarkar, S.Sen Saha Institute of Nuclear Physics, Kolkata S. Chattopadhyay, M.R.Datta Mazumdar, P.Ghosh, G.S.N.Murthy, T.Nayak, Y.P.Viyogi Variable Energy Cyclotron Centre, Kolkata Amitava Raychaudhuri Calcutta University, Kolkata M.V.N.Murthy, D.Indumathi Institute of Mathematical Sciences, Chennai A. Datta, R.Gandhi, S.Goswami, S. Rakshit, P.Mehta Harish Chandra Research Institute, Allahabad S.C.Phatak, D.P.Mahapatra IOP, Bhubaneswar Amit Roy Nuclear Science Centre, New Delhi J.B.Singh, M.M.Gupta, V.Bhatnagar Panjab University, Chandigarh S.D.Sharma Himachal Pradesh University, Simla A.Joshipura, S.Rindani P.R.L., Ahmedabad A.Bhadra,B.Ghosh,A.Mukherjee,S.K.Sarkar North Bengal University S.Umasankar IIT, Mumbai S.K.Singh AMU Scientific Advisors: G.Rajasekaran, Bikash Sinha, Ramnath Cowsik,V.S.Narasimham, H.S.Mani, Amit Roy 41 Experimentalists & Engineers 22 Theorists NSNI-2004, Kalpakkam, February 17-20, 2004
Proposed INO detector • RPC dimension: 3m X 2m • No of chambers: 11K • No of channels: 220K • No of TDC channels: 3K Magnetised iron calorimeter Iron 140 layers RPC 35KTons NSNI-2004, Kalpakkam, February 17-20, 2004
RPC principle of operation NSNI-2004, Kalpakkam, February 17-20, 2004
RPC rate capability NSNI-2004, Kalpakkam, February 17-20, 2004
RPC construction NSNI-2004, Kalpakkam, February 17-20, 2004
A small area RPC prototype Gas inlet Graphite coat Spacer Gas outlet HV terminals NSNI-2004, Kalpakkam, February 17-20, 2004
Cosmic muon trigger and timing NSNI-2004, Kalpakkam, February 17-20, 2004
RPC test setup Cosmic muon telescope NSNI-2004, Kalpakkam, February 17-20, 2004
NIM and CAMAC electronics NSNI-2004, Kalpakkam, February 17-20, 2004
Telescope rate monitoring NSNI-2004, Kalpakkam, February 17-20, 2004
Schematic of gas mixing unit NSNI-2004, Kalpakkam, February 17-20, 2004
Gas mixing unit Argon Iso-butane R134A(Freon) NSNI-2004, Kalpakkam, February 17-20, 2004
Schematic of digital gas bubble counter NSNI-2004, Kalpakkam, February 17-20, 2004
Digital gas bubble counter Temperature and RH meter NSNI-2004, Kalpakkam, February 17-20, 2004
Typical RPC pulse profiles Trigger pulse In streamer mode of operation, pulses are large (>100 mV into 50) and fast (tr < 1ns) X-Strip Y-Strip NSNI-2004, Kalpakkam, February 17-20, 2004
Typical RPC efficiency plot NSNI-2004, Kalpakkam, February 17-20, 2004
Typical timing distribution plots NSNI-2004, Kalpakkam, February 17-20, 2004
Typical time response plot NSNI-2004, Kalpakkam, February 17-20, 2004
Typical time resolution plot NSNI-2004, Kalpakkam, February 17-20, 2004
RPC typical charge distributions NSNI-2004, Kalpakkam, February 17-20, 2004
RPC typical mean charge plot NSNI-2004, Kalpakkam, February 17-20, 2004
RPC pulse height Vs timing plot NSNI-2004, Kalpakkam, February 17-20, 2004
RPC typical noise rate plot NSNI-2004, Kalpakkam, February 17-20, 2004
Typical cross-talk plots NSNI-2004, Kalpakkam, February 17-20, 2004
Summary of cross-talk measurements NSNI-2004, Kalpakkam, February 17-20, 2004
Gas mixtures’ study plots NSNI-2004, Kalpakkam, February 17-20, 2004
Effect of water vapour in gas NSNI-2004, Kalpakkam, February 17-20, 2004
Effect of water vapour in gas NSNI-2004, Kalpakkam, February 17-20, 2004
Recovering a damaged RPC • Purging with pure Argon at high flow rate. • Bubbling pure Argon through pure ethyl alcohol. • Bubbling pure Argon through 25% Ammonia solution for 24 hours without electric field. • Recovers efficiency and brings down noise rate. • Detail studies underway. NSNI-2004, Kalpakkam, February 17-20, 2004
RPC recovery plots No of hours of gas flow NSNI-2004, Kalpakkam, February 17-20, 2004
New RPC test setup 8020 Sections NSNI-2004, Kalpakkam, February 17-20, 2004
INO prototype detector • Detector and signal specifications • Detector dimensions: 1m X 1m X 1m • 14 layers of RPCs with 6cm iron plates interleaved. • Two signal planes orthogonal to each other and each having 32 pick-up strips • Total channels = 32 X 14 X 2 = 896 • Pulse height = 100 to 300mV; Rise time = < 1 ns • Pulse width = ~50ns; Rate ~ 1KHz • Trigger information • Expected trigger rate is few Hz • Required Trigger logic is m X n fold, where • m = 1 to 4; no. of consecutive channels in a layer • n = 5 to 1; no. of consecutive layers with m fold in each layer • ie m x n = (1 x 5) OR (2 x 4) OR (3 x 3) OR (4 x 2) • Information to be recorded on a trigger • Absolute arrival time of the trigger • Track identification (XYZ points in RPC layers) • Direction of track ( TDC information) • Miscellaneous information and calibration data • Monitoring health of the detector NSNI-2004, Kalpakkam, February 17-20, 2004
Readout scheme for prototype NSNI-2004, Kalpakkam, February 17-20, 2004
32-channel front-end module NSNI-2004, Kalpakkam, February 17-20, 2004
Prototype detector trigger logic NSNI-2004, Kalpakkam, February 17-20, 2004
Readout scheme for final detector The keywords are channel count and fast timing NSNI-2004, Kalpakkam, February 17-20, 2004
Current status and future plan • Production and study of small area RPCs successful • Detailed study of effect of water vapour in gas • Repeatability of results and long term stability of RPC • Study of pickup strip materials and geometries • Production of prototype chambers (4 ft X 3 ft) • Gas mixing and distribution system for the prototype detector • Prototype electronics finalised • Production of circuit boards and other components in progress • Initial thoughts given on final electronics and DAQ schemes • Cooperative VLSI and ASIC development programmes explored NSNI-2004, Kalpakkam, February 17-20, 2004