Jefferson Laboratory Hall A SuperBigBite Spectrometer Data Acquisition System Alexandre Camsonne APS DNP 2013 October 24 th 2013 Hall A Jefferson Laboratory

Outline SuperBigbite Spectrometer Experiments Shower trigger Hadron calorimeter digital trigger GEM Fastbus Conclusion SuperBigbite Spectrometer Data Acquisition 10/24/2013 2

SuperBigBite Spectrometer (SBS) 48D48 dipole Large dipole magnet Installation in Hall A Jefferson Laboratory SuperBigbite Spectrometer Data Acquisition 10/24/2013 3

SuperBigBite experiments SuperBigbite Spectrometer Data Acquisition 4 approved experiments GEp5 : Proton Form Factor SBS used as proton focal plane with Hadron calorimeter as polarimeter Neutron form factor GEn and GMn SBS used as sweeper magnet for Hadron Calorimeter as neutron detector Transversity SBS used to detect pions Hadron calorimeter as neutron detector 10/24/2013 4

SuperBigbite Spectrometer G Ep 5 Focal Plane Polarimeter setup SuperBigbite Spectrometer Data Acquisition Most demanding experiment in terms of rate and background ~ cm 2.s -1 10/24/2013 5

Background rate vs. cut on deposited energy (MC studies in progress) Calorimeter Rates HCALECAL Electron rate estimate w/2.5 GeV threshold (73% of E elas ): ≈ 200 kHz Hadron rate estimate using SLAC & DESY data, Wiser code: w/4.5 GeV threshold: ≈ 1.5 MHz ≈ 9 kHz coincidence rate w/ 30 ns window NB: Good resolution ≈ 16%/  E SuperBigbite Spectrometer Data Acquisition From Hall A Real Compton Scattering experiment 10/24/20136

DAQ concept SuperBigbite Spectrometer Data Acquisition Hybrid Fastbus and pipelined electronics Level 1 – ≈100 ns latency by analog summing and discrimination – Generated by electron arm (≈200 kHz rate) – Gate for Fastbus & non-pipelined VME for BigCal Level 2 : coincidence proton in HCAL triggered by ECAL – Assume up to ≈1.8 μs latency ( L2 800 ns max + Fast Clear 1 μs) – 9 KHz with 30 ns coincidence windows – FPGA-based coincidence logic using geometrical constraints reduction by factor 5 ≈ 2 kHz physics DAQ rate – Fast Clear FB & VME after L2 timeout 10/24/2013 7

First level electron trigger from Shower Sum of 8 Summing modules 8 to 1 and linear fan 4 to 1 = sum of 32 Threshold on group of 32 Split signals to have overlapping sums Trigger is OR of all groups of 32 BigCal trigger 200 KHz SuperBigbite Spectrometer Data Acquisition 10/24/2013 8

L2 Hadron calorimeter proton trigger New Hall D type JLAB Electronics – Under development by JLab Electronics and DAQ group – Fully pipelined – 200 kHz L1 trigger rate capability – Synchronous trigger distribution, 250 MHz ref. clock – VME64x front-end crates with support for High-speed readout modes (2eVME, 2eSST) up to 200 MB/s On-module event buffering - up to 200 events Gigabit uplinks to event builder – CODA 3 software – Will use some of this technology + custom modules SuperBigbite Spectrometer Data Acquisition 10/24/2013 9

Digital Hadron Calorimeter HCAL Trigger 12-bit pipelined FADCs CPUCPU TITI SMARTTRIGSMARTTRIG SuperBigbite Spectrometer Data Acquisition x22 modules 242 blocks All channels continuously digitized at 250 MHz Compute all 4x4 sums Generate trigger if sum above threshold Electron trigger Coincidence Electron proton With geometrical correlation ~2KHz 10/24/

e’-p Kinematic Correlation 11 x 22 HCAL blocks 20 x 76 ECAL blocks (CDR section F.3) SuperBigbite Spectrometer Data Acquisition Using geometric correlations from elastic kinematic one can reduce final rate by a factor of 5 and tracker data by at least a factor of 3 10/24/

FPP Tracker layout SuperBigbite Spectrometer Data Acquisition channels 25 ns APV25 40 MHz sampling pipeline chip 192 samples memory depth 128 channels per chip Can transfer 1 or 3 samples 10/24/

MPD APV25 INFN readout Multi Purpose Digitizer FADC GEM readout Up to 16 APV by board 2048 channels / board Latency : t APV = 141 x number_of_sample / 40 MHz = 11 us Buffered VME320 board Adapted software with JLAB Intel VME controller Start optimizing for performance SuperBigbite Spectrometer Data Acquisition 10/24/

Fastbus Reuse older available electronics for rest of detectors – Limitation : encoding 9 us for 1881M ADC, 7.6 for 1877S 40 MB/s – Use several crates to readout modules in parallel Poor man’s pipeline – Use several modules to reduce encoding dead time SuperBigbite Spectrometer Data Acquisition 10/24/

Module flipping SuperBigbite Spectrometer Data Acquisition Trigger Supervisor Trigger PMT L2 L1A Front End Busy Fast Clear Shift register Signal is split analog signal and sent several boards. Readout and trigger are interleaved Fast Clear L2A Shift register ADCs or TDCs Up to 200 KHz L1A rate = 5us Fastbus – ECal 1800 calorimeter channels – BigBite 550 Cerenkov channels 243 Shower/preshower 180 timing scintillators – 3328 scintillator channels – 16 crates – 6 Power Supply  New CODA 3 electronics improve deadtime by 30%  19 controller, 28 crates, 12 PS on hand  TDC and 6208 ADC channels tested 10/24/

Conclusion SuperBigBite DAQ is designed to handle up the rates for Gep 5 : – 200 KHz electron rate – 2 MHz of hadron rate in HCAL – Coincidence and geometrical correlation gives ~2 KHz of trigger rates Readout with GEM with multiple samples allow to clean up background offline in trackers Reuse of Fastbus allows to be ready to run early at reduced cost with reasonable performance SuperBigbite Spectrometer Data Acquisition 10/24/