大亚湾反应堆中微子实验触发和数据获取系统

大亚湾反应堆中微子实验触发和数据获取系统李小男,IHEPOn behalf of触发:清华大学DAQ:IHEP17th 高能物理学会大会,李小男,高能物理研究所sin22q q13 13 Measurement at reactorseeeeeeDistance(L)Probability e1.01500 metersUnoscillatedUnoscillated flux flux observed hereobserved hereWell understood,isotropic source Well understood,isotropic source of electron anti-neutrinosof electron anti-neutrinosOscillations observed Oscillations observed as a deficit of as a deficit of e esinsin2 22 2 1313eeeeeeDetectors are located Detectors are located underground to shield underground to shield against cosmic rays.against cosmic rays.E E /2/2 m m2 2131327th 高能物理学会大会,李小男,高能物理研究所Dayabay Reactor Neutrino Experiment900 m292 m465 m810 m607 mTotal Tunnel length 3000 m37th 高能物理学会大会,李小男,高能物理研究所Detecting eInverse-decay in 0.1%Gd-doped liquid scintillatorAntineutrino signal,algorithm implemented in offline or on online computer farmTime coincidenceEnergy correlated47th 高能物理学会大会,李小男,高能物理研究所Requirements of readout electronicsReadout board designed for all detector systems except RPC.Neutrino detector:Charge measurementDynamic range for each PMT:0 PE -500 PE50 p.e is the maximum for a neutrino event500 p.e.for through-going muonsresolution:10%1 p.e,0.025%400 p.e.Noise 0.1 p.e.Digitization time(mainly shaping time)1 m msTiming measurement:To determine event time and event vertexdynamic range:0 500 nsresolution:500 psMuon detector:Water pool:Same requirements as neutrino detector Water Tracker:Hit and/or chargeRPC:BESIII electronics57th 高能物理学会大会,李小男,高能物理研究所Readout board diagramOn board calibration circuit16 Channel inputsTDC algorithm:Gray counters67th 高能物理学会大会,李小男,高能物理研究所Trigger requirementGood background rejection power rate can go to KHz rate limited by DAQ capabilities(hopefully 10 MB/s/module)Low threshold(T+3s s 15 PEMultiplicity:15 PMT firedVeto trigger:OR of the following twoRPC:two hits in any plane(Scin.1 hits)Water:few PMT firedPrompt and delayed sub-event triggered and recorded independently,time correlation offline Central and veto events triggered and recorded independently,time correlation offline No dead-time induced.Trigger rate is limited by electronics recover time and by DAQ bandwidth.Trigger type:Primary physics triggerLEDRadioactive sourcePeriodic triggerMuon trigger87th 高能物理学会大会,李小男,高能物理研究所PMT dark current ratePMT max.number:200PMT dark current rate:50kIntegration windows:100ns97th 高能物理学会大会,李小男,高能物理研究所Trigger rateDetectorEventTrigger RateOcc.Ch size(bits)DBLAFare ModuleCosmic-36x222x21.2x4100%224*64Rad.50 x250 x250 x4PoolCosmic-25016013.650%340(252)*64TrackerCosmic-139081957.8100%8*64RPCCosmic-26026041510%7650(5040)*1Rad.&Noise18611710.5Site totalskB/s653 4834191555107th 高能物理学会大会,李小男,高能物理研究所Trigger boardOne board per moduleSame hardware design for central and veto boardEach trigger board can handle up to 256 PMTs Decision time:Readout event buffer depthMultiplicity trigger based on FPGA:200 nsEnergy trigger based on total charge:300 ns?System clock+Local clock117th 高能物理学会大会,李小男,高能物理研究所Trigger scheme127th 高能物理学会大会,李小男,高能物理研究所TimingEach site has a master clock to synchronize the veto and central modulesA GPS time/1 PPS/10 kHz reference will be delivered to each site for an absolute time stampIf GPS can not be used,we can use a local clock,a problem for Supernova studies.Precision:GPS time 100 ns.Time-stamp precision level 25ns.Each trigger board have a local clock for self trigger and testing.Mid-siteDYBLAFAR137th 高能物理学会大会,李小男,高能物理研究所DAQ block diagram147th 高能物理学会大会,李小男,高能物理研究所Data acquisition&online controlVME based front-end hardware,Motorola PowerPC controllerRT-Linux RTOS:TimeSys Co.LinuxLink Back-end Linux PC.Software based on BES-III/Atlas FrameworkEach detector system and each neutrino module at each site is readout(trigger)independently.8 antineutrino streams and 9 muon streams.Event reassembled using timestamp offline.One neutrino module One VME crate.Water pool One VME crate(near),Two VME crates(far).Water Cerenkov Module system:TWO VME crates.Communication:Copper between trigger-FEETwisted cable between PowerPC and readout computerOptical between site-site/site-surface.157th 高能物理学会大会,李小男,高能物理研究所Data acquisition and online control Online controlLocal online control in each detector hall:each detector system has its own online control.Detector debugging and commissioning in parallel.Global online control in surface room:Operate and monitor all detector system.Data storage:Data throughout:1.5MB/s.0.4TB/day(safety factor of 3).Local tapesLocal disksData transfer:Tapes from DYB to IHEP or to Shenzhen Uni.A data link from Shenzhen Uni.to IHEP via network can be discussedA data center at IHEP to be established.Raw data or processed data tapes will be copied and shipped to other data centers in the world,or distributed via GRID.167th 高能物理学会大会,李小男,高能物理研究所One Readout VME crate177th 高能物理学会大会,李小男,高能物理研究所StatusSimple version of readout boards and trigger board are successfully running on the prototype.We are working on the 2nd version of readout board and trigger boardWe finished conceptual design of DAQDAQ group is formed and begin to work on the project187th 高能物理学会大会,李小男,高能物理研究所