这项研究了美国能源部doe nnsa国防核不扩散与发展dnn rd支持4 kerisito.pptx

KineticsandEfficiencyofScintillationMechanisms

inHalideScintillatorsAugust18,20241S.Kerisit,D.Wu,andM.PrangePacificNorthwestNationalLaboratory13thInternationalConferenceonInorganicScintillatorsandtheirApplicationsJune9,2015–Berkeley,CAThisresearchissupportedbytheNationalNuclearSecurityAdministration(NNSA),OfficeofDefenseNuclearNon-ProliferationResearchandDevelopment(DNNRD),oftheU.S.DepartmentofEnergy(DOE).

SCINT-2015,Berkeley,CAAugust18,20242MotivationObjectivesComprehensiveunderstandingofscintillationprocesseswillprovideapathwaytooptimizecurrentscintillatorsandsupportthesearchfornewscintillators.CompareandcontrastenergytransferandbinationmechanismsinCsI(Tl),NaI(Tl),andSrI2(Eu).RecentexperimentsatWFUontheexcitationdensitydependenceofthelightyieldwereabletoisolateinteractionsbetweenexcitations.Usephotondensityresponsedatatoparameterizenonlinearquenchingmechanisms.Efficiencyofnonlinearquenchingmechanismsisstronglydependentonthespatialandtemporalscalesoffreecarrierthermalization.Newabinitiotreatmentofrelaxationratesoffastparticlesbyphonons.

SCINT-2015,Berkeley,CAAugust18,20243KineticMonteCarloAlgorithmAtomic-levelsimulationofthekineticsandefficiencyofscintillationprocesses.k=A×exp(-W/kBT)x1andx2arerandomnumbers3Dsimplecubiclatticeisgenerated.Latticepoint≡atomorunitcell.Activatorsareplacedrandomlyonthelattice.e-hpairdistribution:homogeneous,exponentialdecayfromsurface,orfromionizationtrackcalculations.STH/STEdiffusiontreatedasrandomwalk.Foreachprocess,2parametersareneeded(AandW)tocomputerateatalltemperatures:ProcessesDiffusion(STHsandSTEs).Radiativeandnon-radiativedecay(STEs,activators,andimpurities).Electronthermalrelease.Excitondissociation.2nd-and3rd-orderinteractions(exceptions).

SCINT-2015,Berkeley,CAAugust18,20244Kinetics