tpc electronics calibration with pulser in cold box data

TPCelectronicscalibrationwithpulserincoldboxdata

DavidAdamsBNL

June20,2018

BNLDUNE

IntroductionIlookatAPAdatafromCERN

•  DataavailableatCERNandFNALo  https://wiki.dunescience.org/wiki/Accessing_ProtoDUNE-SP_Cold_Box_Test_Data_in_LArSoft

•  SingleAPAinacoldboxo  Expecttofind2560channels:20FEMB×128chan/FEMBo  ForAPA5testing,12/20FEMBshavedataè1536channels

•  Somedatatakenwithpulsero  DAC=1,2,…,10(Seefollowingpage)

•  UsethisdatatocalibratetheTPCelectronicso  I.e.convertADCcounttoinputcharge

D.Adams,BNLDUNEDRACalibrationwithpulsersignalsincoldboxdataJune20,2018 2

PulserPulser

•  DACusedinducevoltageshiftVinatinputtopreampo  (Asdoesamovingchargeinthevicinityofananodewire)o  Voltageshiftedupandthenbackdownperiodicallyo  Risingandfallingedgesinjectcharge

•  WithknowninputcapacitanceC,thechargeinjectionisQin=CVino  DACsettingofP=0,1,2,…,63shouldgiveVin=PVstep

èQin=PQstepwhereQstep=CVstep=(183fF)(18.75mV)=3.43fC=21.4ke

•  Twooptionsforthepulsero  Internal:DACisonthepreampASICo  External:DAContheFEMB

•  APA5datatakenwithinternalpulsero  Behaviordoesnotfollowtheaboveidealo  Thereisachannel-dependentoffset:Vin=Voff+PVstepforP>1o  P=1hasadditionalchanneldependenceo  IgnoreP=1and,forP>1,assumeQin=Qoff+PQstep


P=1isabout1MIP

AnalysisprocedureForeachchannelandpulsersetting

•  Evaluateandsubtractpedestal•  FindROIs

o  ROI=regionofinterest,rangeoftickswheresignalappearo  OneROIshouldbeonepulse,i.e.astepupordownintheinputvoltageo  Simplethresholdalgorithmissufficienttofindthesepulseswhichare

wellabovethenoiselevel•  ProcessROIs

o  Separateanalysisforpositiveandnegativesignalso  FiteachROIwithcoldelecfunction

–  Varyheight,shapingtimeandpositioninfito  Createsummaryhistogramswiththemeanvaluesof

–  height–  shapingtime–  chi-square–  chi-square/DOF

•  Samplefclinappendix(usesTool-baseddataprep)Evaluategainforeachchannel

•  Usingobservedheightdistributionsformultiplepulsersettings


ExampleROIfits(run1193,pulser=3)


Examplesummaryheightandshaping(1/1200)


Pos.pulses

Neg.pulses

Examplesummarychi-square(1/1200)


PulsefitqualityFollowingslidesshowfitqualityfor200channels

•  Meanvaluefromdistributionslikethoseonpreviouspage•  Forthe7differentDACsettings•  Twoplots

o  Rawchi-square(fromfitwithouterrors)o  Normalizedchi-squaredividingbyDOFandusingthepedestalRMSasthe

uncertaintyforeachADCbin•  Resultsverygoodforpositivepulses

o  Correctedmeanchi-square/DOFisclosetooneexceptatthehighestDACsettingwheresaturation(clipping)isevidentbyeye

•  NegativepulsequalitydegradesasDACsettingisincreasedo  Notclearwhythisis


FitqualityforDAC=2


CrossesarepositivepulsesCirclesarenegativepulses

FitqualityforDAC=3


FitqualityforDAC=4


FitqualityforDAC=5


FitqualityforDAC=6


FitqualityforDAC=7


GainevaluationUsepulserdatatomeasuregains

•  I.e.ADCcountoutforagiveninputchargeo  Inputchargefollowsfromtheheightofthepulservoltagestep

•  Usingprecedingmodelforinputcharge,expect(ADC–pedestal)A=gQin=g(Qoff+PQstep)=S(P+Poff)QstepgwhereS=+1fortherisingedgesand-1forthefallingedges•  Fitforg(andPoff)usingmeasuredAforP=2,3,…

o  Stopwhenpulsesaturates(amplifierorADC)o  LargervaluesofPmayidentifylimitsofADCrange

•  AisthemeanoftheheightforDACsettingPo  RMSofthisisusedaserrorinAforthefit


Gainfits


Gainandoffsetfitsresultsvs.channel


Fitqualityvs.channel


DAC=2looksbadhere

Fitdistributions(channels500-699)


12.8ADC/keRMS=3.2%

Summary/conclusionsPulserdatausedtoobtainTPCelectronicscalibration

•  Thegain,(inputcharge)/(ADCcount),foreachchannelo  Sofarfor200inductionchannelso  Datatakenwithpreampgainof25mV/fCand2μsshapingo  Resultisanaveragegainof78e/(ADCcount)withσ=3.2%

•  Pedestalwasevaluatedfirst(seeearliertalks)•  GainisanaverageoverabroadrangeoftheADC

o  Moreworkneededtocorrectfornon-linearityorgetresponseinthesingleMIPregion

o  Pulsesalonegiveonlycoarsecalibrationo  Butmaybeabletousepointsonthepulsewaveformtogofiner

Aboveisapulseheightcalibration•  Validforisolatedsignalwithchargecollectiontime<<2μs•  Ithinkwewantapulseareacalibration—right?

o  Straightforwardtoobtainthisfrompulserdata

•  Abitmorechannel-to-channelvariationbecauseshapingtimevariesD.Adams,BNLDUNEDRACalibrationwithpulsersignalsincoldboxdataJune20,2018 32

FutureStudyfew%ofchannelswithpoorfitsLookatremainingchannelsinAPA5

•  Theother1336channels•  Includingcollectionwithdifferentpedestallocation

Areacalibration?Calibrate

•  PutgainsincalibrationtoolandvalidateSearcheachchannelforstickyADCcodes

•  Determineextentoftheproblemo  Usepulserdatatodetermineimplicationwithandwithoutmitigation

•  Mostofthedataisisinthepedestalregionandwecandoathoroughcharacterizationthere

•  Usesamplesalongthepulsewaveformtoexamineotherregionso  VarypulserDACandoffsettoilluminatemostoftheADCrangeo  Goodfitqualitysuggeststhiswillworkwellforthepositivepulseso  LiketounderstandwhyfitqualitydegradesfornegativepulsesathighDAC

settings


Extras


RawDigitPrepService: { service_provider: ToolBasedRawDigitPrepService LogLevel: 3 DoWires: false AdcChannelToolNames: [ "digitReader", "adcPedestalFit", "pdapa_adcChannelPedestalRmsPlotter", "adcSampleFiller", "adcThresholdSignalFinder", "adcRoiFitterPos”, "adcRoiFitterNeg" ] }

Dataprepserviceconfiguration


Extractrawdataandpedestalfromraw::RawDigitFindpedestals

Subtractpedestal,trivialcalibration

ProcessROIs

FindROIs

DisplayRMS

ConfigurationofROIprocessingtool(obsolete)tools.adcRoiFitterPos: @local::tools.adcRoiFitter tools.adcRoiFitterPos.LogLevel: 2 tools.adcRoiFitterPos.SigThresh: 100.0 tools.adcRoiFitterPos.RoiHistOpt: 1 tools.adcRoiFitterPos.FitOpt: 1 tools.adcRoiFitterPos.RoiRootFileName: "roiroipos.root" tools.adcRoiFitterPos.SumRootFileName: "roisumpos.root" tools.adcRoiFitterPos.ChanSumRootFileName: "roichanpos.root" tools.adcRoiFitterPos.SumHists: [ {var:fitHeight name:"hfh_ch%0CHAN%" title:"ROI fit height channel %CHAN%" nbin:100 xmin:100 xmax:5 fit:gaus}, {var:fitHeight name:"hfhw_ch%0CHAN%" title:"ROI fit height channel %CHAN%" nbin:100 xmin:0 xmax:0 fit:gaus}, {var:fitWidth name:"hfw_ch%0CHAN%" title:"ROI fit width channel %CHAN%" nbin:100 xmin:4.0 xmax:4.5 fit:gaus}, {var:fitWidth name:"hfww_ch%0CHAN%" title:"ROI fit width channel %CHAN%" nbin:100 xmin:0.0 xmax:0.0 }, {var:fitPosition name:"hfp_ch%0CHAN%" title:"ROI fit position channel %CHAN%" nbin:100 xmin:0.0 xmax:10000 }, {var:fitTickRem name:"hfr_ch%0CHAN%" title:"ROI fit position remainder channel %CHAN%" nbin:100 xmin:-0.5 xmax:0.5 fit:gaus}, {var:fitPeriodRem name:"hftw_ch%0CHAN%" title:"ROI fit period remainder channel %CHAN%" nbin:500 xmin:-250 xmax:250 }, {var:fitChiSquare name:"hfcsw_ch%0CHAN%" title:"ROI fit #chi^{2} channel %CHAN%" nbin:100 xmin:0.0 xmax:0.0 }, {var:fitCSNormDof name:"hfcsndw_ch%0CHAN%" title:"ROI normalized fit #chi^{2}/DOF channel %CHAN%" nbin:100 xmin:0.0 xmax:0.0 } ] tools.adcRoiFitterPos.ChannelRanges: [ {name:apa1u begin:0 end:800 label:"APA1u"} ] tools.adcRoiFitterPos.ChanSumHists: [ {name:"hcsHeight_%CRNAME%" title:"ROI fit height run %RUN% %CRLABEL%" valHist:"hfh_ch%0CHAN%" valType:fitMean cr:apa1u}, {name:"hcsShaping_%CRNAME%" title:"ROI fit shaping time run %RUN% %CRLABEL%" valHist:"hfw_ch%0CHAN%" valType:fitMean cr:apa1u}, {name:"hcsChiSquare_%CRNAME%" title:"ROI fit #chi^{2} run %RUN% %CRLABEL%" valHist:"hfcsw_ch%0CHAN%" valType:mean cr:apa1u}, {name:"hcsCSNormDof_%CRNAME%" title:"ROI fit Normalized #chi^{2}/DOF run %RUN% %CRLABEL%" valHist:"hfcsndw_ch%0CHAN%" valType:mean cr:apa1u} ]


Summaryhistograms

Channelsummaryhistograms

OutputrootfilesFitwithcoldelecfunction

tpc electronics calibration with pulser in cold box data

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