B.Satyanarayana (For INO collaboration) Department of High Energy Physics Tata Institute of Fundamental Research Homi Bhabha Road, Colaba, Mumbai, Proposed detector and data readout system for the India-based Neutrino Observatory(INO)

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, 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

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, 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

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, 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 INO Collaboration 41 Experimentalists & Engineers 22 Theorists

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, Proposed INO detector Magnetised iron calorimeter Iron RPC 140 layers RPC dimension: 3m X 2m No of chambers: 11K No of channels: 220K No of TDC channels: 3K 35KTons

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, RPC principle of operation

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, RPC rate capability

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, RPC construction

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, A small area RPC prototype Gas inlet HV terminals Graphite coat Gas outlet Spacer

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, Cosmic muon trigger and timing

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, RPC test setup Cosmic muon telescope

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, NIM and CAMAC electronics

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, Telescope rate monitoring

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, Schematic of gas mixing unit

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, Gas mixing unit Argon Iso-butane R134A(Freon)

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, Schematic of digital gas bubble counter

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, Digital gas bubble counter Temperature and RH meter

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, Typical RPC pulse profiles Trigger pulse In streamer mode of operation, pulses are large (>100 mV into 50  ) and fast (t r < 1ns) X-Strip Y-Strip

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, Typical RPC efficiency plot

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, Typical timing distribution plots

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, Typical time response plot

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, Typical time resolution plot

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, RPC typical charge distributions

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, RPC typical mean charge plot

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, RPC pulse height Vs timing plot

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, RPC typical noise rate plot

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, Typical cross-talk plots

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, Summary of cross-talk measurements Gas MixtureSlit Size (mm) Cross talk (%) 62:8: :8: :8: :8: :8: :8:

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, Gas mixtures’ study plots

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, Effect of water vapour in gas

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, Effect of water vapour in gas

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, 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.

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, RPC recovery plots No of hours of gas flow

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, New RPC test setup 8020 Sections

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, 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

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, Readout scheme for prototype

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, channel front-end module

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, Prototype detector trigger logic

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, Readout scheme for final detector The keywords are channel count and fast timing

B.Satyanarayana, TIFR, MumbaiNSNI-2004, Kalpakkam, February 17-20, 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