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Learning with PurposeLearning with Purpose
C7LYCforNeutrons
ParthaChowdhuryUniversityofMassachusettsLowell
WorksupportedbyU.S.DepartmentofEnergy
Learning with Purpose
• Uniquedualn-g scintillatorCs2LiYCl6 (CLYC)
• n-g discriminationandspectroscopicproperties
• Fastneutronspectroscopywith7Li-enrichedC7LYC
• BenchmarksciencecapabilitieswithC7LYCarray
• Largercrystalsizesandefficiencymeasurements
• AuxiliaryscintillatorforFRIBscience?
Overview
Chowdhury FRIB Decay Station Workshop Jan 25, 2018
Learning with Purpose
novelscintillatorforfastneutronspectroscopy
En = 1 MeV
Chowdhury FRIB Decay Station Workshop Jan 25, 2018
Learning with Purpose
• GammaresponsebetterthanNaI• Excellentn-g pulse-shapediscrimination• ~10%neutronpulseheightresolution• NoToF needed,increasedgeometricalefficiency
• Explorefastneutronspectroscopypotential• Eliminated6Li(n,a)peakvia7Li-enrichedC7LYC• Builta16-elementarrayof1”x1”C7LYC
(largestcrystalsavailableatthetime)
• Elastic/inelasticneutronscatteringatLosAlamos• Beta-delayedneutronspectroscopyatCARIBU• EfficiencyandlowenergymeasurementsatUML
C7LYCfornuclearscience
Chowdhury FRIB Decay Station Workshop Jan 25, 2018
Learning with Purpose
56Fe(n,n’)atLANSCE
Chowdhury FRIB Decay Station Workshop Jan 25, 2018
Learning with PurposeLearning with Purpose
En > 0.9 MeV
En > 0.0 MeV
100keV slicesonincidentneutronenergy56Fe(n,n’)atLANSCE
Chowdhury FRIB Decay Station Workshop Jan 25, 2018
Learning with PurposeLearning with Purpose
100keV slicesonincidentneutronenergy
En > 1.9 MeV
En > 1.0 MeV
56Fe(n,n’)atLANSCEChowdhury FRIB Decay Station Workshop Jan 25, 2018
Learning with PurposeLearning with Purpose
100keV slicesonincidentneutronenergy
En > 2.9 MeV
En > 2.0 MeV
56Fe(n,n’)atLANSCEChowdhury FRIB Decay Station Workshop Jan 25, 2018
Learning with PurposeLearning with Purpose
100keV slicesonincidentneutronenergy
En > 3.9 MeV
En > 3.0 MeV
56Fe(n,n’)atLANSCEChowdhury FRIB Decay Station Workshop Jan 25, 2018
Learning with Purpose
MCNPXefficiency“estimates”
1”
LargeuncertaintyinMonteCarlosimulations35Cl(n,p)cross-sectionmeasurementslacking
Chowdhury FRIB Decay Station Workshop Jan 25, 2018
Learning with Purpose
35Cl(n,p)cross-sections
ENDF/B-VII.1(2011)ENDF/B-VII.0(2006)
LANL-ledexperiment(Jan2018)tomeasure35Cl(n,p)cross-sections
Chowdhury FRIB Decay Station Workshop Jan 25, 2018
Learning with Purpose
relativecross-sectionestimates
Chowdhury FRIB Decay Station Workshop Jan 25, 2018
Ramirezetal,PRC95,064605(2017)
Elastic
Inelastic(21+)
~60mb/sratminimum
~60mb/sraverage
Learning with Purpose Chowdhury FRIB Decay Station Workshop Jan 25, 2018
relativecross-sections(expt 1)
presentdata(50-keVslicewitharbitrarynormalization)comparedwithsimulations/databaseforelasticangulardistributioncross-sections)
Learning with Purpose Chowdhury FRIB Decay Station Workshop Jan 25, 2018
relativecross-sections(expt 2)
presentdata(50-keVslicewitharbitrarynormalization)comparedwithsimulations/databaseforelasticangulardistributioncross-sections)
Learning with Purpose
b-delayedneutrontrialsatCARIBU
GammabackgroundinCARIBUhall
PRESENT
FUTURE
Chowdhury FRIB Decay Station Workshop Jan 25, 2018
(CLYCresultsinconclusive,toberepeatedinnewlow-backgroundCARIBUhall)
Learning with Purpose
thefirst3”x3”C7LYC
Active volume Array X 1.7
Chowdhury FRIB Decay Station Workshop Jan 25, 2018
Learning with Purpose
thefirst3”x3”C7LYC
3” x 3” C7LYC
1” x 1” C7LYC
3” x 3” C7LYC (blue)
3” x 3” NaI (red)
C7LYC Efficiency 98% of NaIC7LYC FWHM 5.8%
NaI FWHM 7.8% 137Cs
661 keV
Chowdhury FRIB Decay Station Workshop Jan 25, 2018
Learning with Purpose
C7LYCtestsatUMassLowell
✦DirectlymeasureC7LYCefficiencyataccelerator✦Mono-energeticneutronsvia7Li(p,n)7Be✦Neutronproductionratevia7Beassay(52-dayhalf-life)✦One7Beperneutron,10%b-decaybranch,479-keVg-ray
1” x 1
3”x 3”
In-situ lithium target evaporator
Chowdhury FRIB Decay Station Workshop Jan 25, 2018
Learning with Purpose
C7LYCtestsatUML
7Li(p,n)7Be (g.s)
7Li(p,n)7Be*
Neutrongatedspectrum
3”x 3”
DE=429keV
Neutronenergy(keV)
En = 2 MeV
En = 1.5 MeV
En = 1 MeV
En = 0.5 MeV
En = 0.25 MeV
Chowdhury FRIB Decay Station Workshop Jan 25, 2018
Learning with Purpose
• BenchmarkC7LYCforfastneutronspectroscopy• LANL(n,n’)experimentsverypromising• MeasureefficiencyandlowenergyresponseatUML• Explore(d,n)spectroscopyatUML• ExplorePSD+TOFforlowenergyneutrons• 35Cl(n,p)cross-sectionmeasurements(LANLlead)• Detailedsimulationswithmeasuredcross-sections• Beta-delayedneutronexperimentsatnewCARIBUhall• Optimizen-gammacoincidencecapabilitieswitharray• Testasauxiliarydetectorwithlargegammaarrays
statusandoutlook
Chowdhury FRIB Decay Station Workshop Jan 25, 2018
Learning with Purpose
UMassLowellTristanBrown,EmeryDoucet,KimLister,GemmaWilson,
ChrisMorse,AndrewRogers,NathanD’Olympia,AlanMitchell,EmilyJackson
LosAlamosMattDevlin,JaimeGomez,Shea Mosby,RonNelson
SupportedbyU.S.DepartmentofEnergyNNSA-SSAPGrantDE-NA0002932 and
OfficeofScienceGrantDE-FG02-94ER40848
THANKYOU!
Collaborators
Chowdhury FRIB Decay Station Workshop Jan 25, 2018
