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Overview of the current TDR system. Introduction Electronics for instrumentation TDR core : Metronome, ADC, Merge Data Handling. Pete Jones, University of Jyväskylä SAGE / LISA Kick-Off Meeting Daresbury Laboratory, 2nd September 2005. TDR (Total Data Readout).
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Overview of the current TDR system • Introduction • Electronics for instrumentation • TDR core : Metronome, ADC, Merge • Data Handling Pete Jones, University of JyväskyläSAGE / LISA Kick-Off MeetingDaresbury Laboratory, 2nd September 2005
TDR(Total Data Readout) • Collects data from all detectors (over 500 channels and timestamps arrival to 10ns accuracy) and keeps it synchronised • Timestamping ADCs : Measure energy + time of arrival of signal. • All possible data is therefore collected
C F D A D C A M P Electronics • Each detector pre-amp output to electronics racks • Amplifier : TFA / CFD combination – ADC Gate • Amplifier : Shaping amp – ADC input • Logic signals to user electronics, TACS • 4 free channels (x16) w/o JUROGAM
Electronics • Linear amplifer suffer decreased resolution for counting rates > 3kHz • CFD/TFA gives good response at counting rates 0-100kHz • Large number of high count rate spectroscopy channels C F D A M P A D C AMP
E T1 T2 TDR ADC • VXI Card with 32 independent channels (analogue input + gate) • 14 bit, 0-8V, 4.5us conversion time, sliding-scale : 16k spectra • Flexible gating conditions can be programmed / Veto inputs • Generates timestamp from gate and converts • Output of data via SHARC link • JUROGAM uses 2 cards -> 64 channels available Detect and measure ”pileup” by second pulse : two timestamps Fast Decays / Ge pileup - TDR
TDR Pattern Register • VME Card with 32 independent channels • Different operating modes for eg. Fast veto, grouped modes • Flexible input signals • Generates timestamp from inputs • Output of data via SHARC link
TDR Metronome • Heart of the TDR system • Master 100MHz clock for ALL TDR components • Generates SYNC pulses (every 655us) + fast starts whole system • Battery backup of clock counter • 8 outputs, currently 3 free 100 MhZ Distribution through cables SYNC Pulse Distribution
DATA COLLATE Data from each ADC card is time ordered, but COLLATE these together to produce time ordered data per SHARC & Over all sharcs S H A R C ADC ADC S H A R C ADC TIME ORDERED DATA
How TDR works : DATA MERGE • Data from all COLLATORS are MERGED together and time ordered. C O L LA T O R C O L LA T O R M E R G E C O L LA T O R C O L LA T O R
Collate / Merge • VME Based 3 processor system • Merge CPU takes data from 2 collate CPUs, time orders, histograms • Output via Gbit ethernet to Event Builder • Processes up to 2Mevents/s, or 16MByte/s
GAS Si Si 2us Event Builder • Once data are correlated by Event Builder, data selections can be processed in flexible way. • Data can be output to several destinations • Data Selection Reduce raw singles data to useful coincidence data JUROGAM PU / BGO supression
Data Storage / Analysis • Selected data (i.e. anything with GREAT) sent to DataStore • 2TB Raid 1 array + redundancy – accessable from Gbit network • Data also available by online & offline workstations • User decides how to store data : Disc, Tape, etc.
Overview of the current TDR system • ~400 channels of electronics • Over 500 channels of analogue / digital inputs into TDR • Stable metronome with master 100MHz clock • VXI / VME based core of acquisition • PC based Merge / Online / Offline systems • Stable environment for electronics & acquisition • Extremely stable for experiments, over 3 months continual running without fault