CONTACT: =ichaelOWagenpfeil IrlangenOHentreOforOUstroparticleO+hysics michaelTwagenpfeilBfauTde SEEgALSO: StudyOofO+hotonOtransportOandOSi+= inOexternalOelectricalOfieldOinOnIX; &rTO+inO°Vi)OidqOV2?6 CharacterizationgofgVUV@ sensitivegSiPMsgforgnEXO MichaelgWagenpfeilO0forOtheOnIX;Ocollaboration5 id:g#439 PhysicsgbeyondgStandardgModel? •OTheOneutrinolessOdoubleObetaOdecayO 05opensOwindowOtoOphysicsObeyondOS= •OUreOneutrinosO=ajoranaOparticlesN •OHurrentO?νββOsearchesOareOsensitiveO 05toOaOhalf•lifeOofOaboutOv?-[OyearsO[v)O-] •OnIX;OplansOtoOincreaseOsensitivityO[1] ThegnEXOgdetectorO[1)O2] •OTime•projection•chamberO0T+H5OfilledOwithO~O6 tonsOOO 05ofOliquidOXenonO0°Xe5O–OenrichedOtoO~? :OinOv1[Xe •OHylindricObarrelOwithOaOdiameterOandOheightOofOvT1 m •O&etectorOsetOupOinOundergroundOlabOtoOshieldOfromO 05cosmicOraysO0likelyOS/;°UG)O[??? mweT5 •OSignalOdetectionOviaOchargeOreadoutOtilesO0endOcap5O 05andOVUV•sensitiveOSi+=sO0innerOcylinderOsurface5 •OHathodeOsetOtoO•6? kVOtoOproduceOaxialOdriftOfieldOO •OIxtensiveOradiopurityOscreeningOtoOconstrainOG8 •OQomogeneousOdetectorO#Omulti•parameterOanalysis Lightgdetection •OnIX;OsensitivityOdependsOonOphotonOtransportO 05efficiencyOandOphotonOdetectionOefficiency •ORnsideOwallOcoveredOwithO2 m-OofOVUV•sensitiveOSi+=s •O&etectionOofOv]3 nmOscintillationOlightOinO°Xe •O8oalqOv :OenergyOresolutionOatOµ•valueO0-263 keV5 •OStrongOrequirementsOonOSi+=OparametersO SiPMgcharacterizationgtestgsetups •OIHU+)OIrlangenO0&arkOnoise)O+&I)OVUVOreflectance5 •ORQI+)OGeijingO0QVObehaviour)OVUVOreflectance5 •OTzRU=7)OVancouverO0&arkOnoise)O+&I5 •OUU)OUlabamaO0VUVOreflectance5 •OStanfordO0+&I)OSi+=Otiles5 •OU=assO0+&I)O°Xe5 VariousgSiPMs •OQamamatsuOVUV1)OVUV2 •O7GKO/UVO-?v[O°7O#OST& 7romOleftOtoOrightq TestOsetupOatOIHU+)OtestOsetup atOStanford)OQVOsetupOatORQI+ •OzecordOSi+=OdarkO 05pulsesOatO•v??°H •O7itOpulseOtemplateO 05toOwaveforms •OUseOamplitude)O 05timestamp)OriseO#O 05fallOtimeOforOanalysis Afterpulsing •O&elayedOavalanchesOcorre• 05latedOtoOtheOprimaryOpulse •ORmportantOnuisanceOchargeO 05contribution PDE •OIfficiencyOtoOdetectOsingleO 05photons •OUngle•)Owavelength•OandO 05biasOvoltage•dependent •OnIX;OrequirementsOmet nEXOgenergygresolution •O&ependsOonO+&IO#OphotonO 05transportOefficiencyO0+TI5 •O+lotOshowsOcaseOofO+TI%?T-OOOOO 050electronicOnoiseOneglected5 •OzesolutionOgoalOachievable SiPMgHVgrobustness •OSi+=sOwillObeOexposedOtoOexternalOelectricO 05fieldsOupOtoO-? kVjcmOinOnIX;OaccordingOtoO 05H;=S;°Osimulations •O&etectorsOfoundOtoObeOoperationalOinOhighO 05electricOfieldsOatOcryogenicOtemperatures •OGasicOparametersOunaffected–O/oOdischarge •O/oOdamageO•OevenOonOaOmicroscopicOlevel Measuringgprocedureg@gECAP Measuringgprocedureg@gStanford •OzecordO+=TOandOSi+=OpulsesOfromO-6-Hf •OHalibrationOofOsingleOphotonOresponses •OIxtractOchargeOratioOofOtheOdecayO 05spectrumOpeaks •OTranslateOinto 05absoluteO+&I 05usingOtheO+=T 05referenceOµI •OUccountOfor5cor• 05relatedOnoise [v]OUgostiniOetTOalT)Ov]?6T?-~~[ [-]OIX;•-??•HollT)OarXivqv]?]T?3]?] [1]qOnIX;•HollT)OarXivqv]v?T?6?]6 [-]qOnIX;•HollT)OarXivqv3?6Tvvv2- Wb Wb e e ? 6 v? v6 -? -6 1? ? ?T- ?T2 ?T[ ?T3 v vT- +hoton detection eﬃciency [:] Udditional avalanches within vµs °7 Sv °7 S- ST& S ?T] ?T3 ?T~ v vTv vT- vT1 vT2 ? v - 1 2 6 [ Inergy resolution [:] ;vervoltage [V] °7 Sv °7 S- ST& S ? v - 1 v?? v?v v?- v?1 v?2 prompt crosstalk prompt delayed crosstalk afterpulsesOand darkOnoise 0afterpulsesOand darkOnoise5Osuffering promptOcrosstalk afterpulsesOsuffering promptOcrosstalk afterpulses Hharge [pTeT] Time after trigger [ns] ? v - 1 v?? v?v v?- v?1 v?2 v?? v?v v?- /umber of events v?? v?v v?- v?1 v?2 v?6 v?[ v?] v?? v?v v?- v?1 v?2 v?6 v?[ v?] v?3 v?~ +ulse rate [Qz] Time to next pulse [ns] ]Tv V 2T[ V 1T[ V [kVjcm] I ? 6 v? v6 -? -6 1? 8ain η ?T3 ?T36 ?T~ ?T~6 v vT?6 vTv vTv6 vT- 7GK•z8G 7GK•lowOfield QamamatsuOVUV1 relativeOSi+=O8ain [kVjcm] I ? 6 v? v6 -? -6 1? H/ + η ?T3 ?T36 ?T~ ?T~6 v vT?6 vTv vTv6 vT- 7GK•z8G 7GK•lowOfield QamamatsuOVU