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Status of The D0 Calorimeter. Nirmalya Parua. (For the Calorimeter Group). General Overview. 55k channel Ur/liq. Argon calorimeter Run II upgrade: replacement of electronics to accommodate faster bunch crossings 55k dual FET PreAmps 23k Switch Capacitor Arrays (SCA) on
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Status of The D0 Calorimeter Nirmalya Parua (For the Calorimeter Group)
General Overview • 55k channel Ur/liq. Argon calorimeter • Run II upgrade: replacement of electronics to accommodate faster bunch crossings • 55k dual FET PreAmps • 23k Switch Capacitor Arrays (SCA) on • 1200 BaseLineSubtraction (BLS)-boards ~ 50 bad channels (~0.1%) Bank 0 Trig. sum Calibration electronics readout chain SCA (48 deep) SCA (48 deep) x1 Filter/ Shaper Output Buffer Preamp/ Driver SCA BLS x8 Calorimeter SCA (48 deep) SCA (48 deep) Bank 1 All Experimenters meeting
Installation & Commissioning • Only Remaining piece is Trigger readout for ||>0.8 • We have occasional failure of power supplies.
…. …. ADC counts L1 SCA up … … L1 SCA down L2 SCA Finer Debugging R. Zitoun, Stony Brook x8 down L1 SCA up x1 L2 SCA ADC • Most problems are traced to slower SCA chips. • More than 250 are replaced Mean value
Broken cable various detector capacitances Feedthrough PreAmp-Cryostat Cable Impedance Measurement Paris & Orsay A total 31 channels are not connected
Timing Studies • M. Gao, Columbia, NY • • Nominal 132 ns later • Pedestal Values were different for Early, Nominal or Late sampling. • Corrected after putting additional CAPS on BLS boards. 132 ns early Sampling time vs amount sampled • -50 ns 98.01% • -20 ns 99.69% • -10 ns 99.92% • 10 ns 99.93% • 20 ns 99.71% • 50 ns 98.23% Nominal sampling time varies from –6 ns to 35ns
Online Data Quality Check • Shifter’s are continuously monitoring quality of data. • When hot cells are found corresponding readout channels are suppressed. N.Parua
pulser shaper output ADC pulser ADC readout 8 1 Pulser Calibration S. Beauceron Pulser signal injected here (measured in DAC counts) saturation R. Zitoun • Non linearity <0.3% for DAC>1000 • For Lower DAC values non linearity is parametrized (same for all channels). DAC/1000
W/Z candidate Em Cluster with track Chan, Zutshi Invariant Mass Transverse mass kado, zitoun Yuri Gerstein
Multi jet events A. Kupco • 3-jets event • ETjet1~310GeV • ETjet2~240GeV • ETjet3~110GeV • ET~8GeV • 2-jets event • ETjet1~230GeV • ETjet2~190GeV
Jet Energy Scale Two-jet Events Et=27 GeV Energy Density for Min-bias Data Et=24 GeV Ia Iashvilli N. Parua, J. Coss, S. Muanza