Gas Gain vs.High Voltage Geiger Counter Limited Proportional Region MWPC Geiger-Muller Region Proportional lon Region Saturation MRPC 1 1 Applied Voltage 2023/6/28 Talk for EM group 伍健 11
2023/6/28 Talk for EM group 伍健 11 Gas Gain vs. High Voltage MWPC MRPC Geiger Counter
9 Multi-Wire Proportional Chamber(MWPC) YCathode Cathode E field Anode wires lines 色的 Avalatche Cathode 1、.」 △=wire Cathode spacing G.Charpak,1992 Nobel Prize for invention and application of MWPC in 1968 2023/6/28 Talk for EM group伍健 12
2023/6/28 Talk for EM group 伍健 12 Multi-Wire Proportional Chamber (MWPC) G .Charpak, 1992 Nobel Prize for invention and application of MWPC in 1968
Resistive Plate Chamber conductive anode resistive anode E E dead area dead area Fast trigger,good time resolution (<100ps for 300um gap in streamer mode,~1ns for 2mm gap in avalanche mode),high rate capacity (>104sicm-2) 2023/6/28 Talk for EM group伍健 13
2023/6/28 Talk for EM group 伍健 13 Resistive Plate Chamber Fast trigger, good time resolution (<100ps for 300m gap in streamer mode, ~1ns for 2mm gap in avalanche mode), high rate capacity (>104s -1cm-2 )
Simulation Procedure-step by step Set time step dt and position step dx dt'vdrift Get primary cluster position (exponential distribution) according to cluster density Get primary cluster size following the size distribution For each electron in each cluster,multiplies following Townsend's law and the avalanche fluctuation distribution(include space charge effect) ◆ Calculate the signal induced by using Ramo's theorem ◆ Induced current is convolved with FEE response,then passes to discrimination to provide TDC timing,ADC is also calculated 2023/6/28 Talk for EM group 伍健 14
2023/6/28 Talk for EM group 伍健 14 Simulation Procedure - step by step Set time step dt, and position step dx = dt·vdrift Get primary cluster position (exponential distribution) according to cluster density Get primary cluster size following the size distribution For each electron in each cluster, multiplies following Townsend’s law and the avalanche fluctuation distribution (include space charge effect) Calculate the signal induced by using Ramo’s theorem Induced current is convolved with FEE response, then passes to discrimination to provide TDC timing, ADC is also calculated
RPC Application-ATLAS Muon Trigger System Reslstive plate chambers MDT chambers Barrel toroid coils End-cap X Bakelite Grounded toroid Plates Foam Gas readout plane strips S HVI Graphite PET Y Calorimeters Inner detector electrod spacers readout es strips Gas mixture:C2H2F4 94.70/-C4H10 5%-SF60.3% Avalanche regime 2023/6/28 Talk for EM group伍健 15
2023/6/28 Talk for EM group 伍健 15 RPC Application – ATLAS Muon Trigger System HV Bakelite Plates Foam X readout strips Gas Graphite electrod es PET spacers Y readout strips Grounded plane Gas mixture: C2H2F4 94.7% - C4H10 5% - SF6 0.3% Avalanche regime