nuclear science with a c lyc array - orau.gov · learning with purpose cs 2 liycl 6 (clyc): novel...

Learning with PurposeLearning with Purpose

NuclearSciencewithaC7LYCArray

ParthaChowdhuryUniversityofMassachusettsLowell

WorksupportedbyU.S.DepartmentofEnergy

Learning with Purpose

Cs2LiYCl6 (CLYC):noveldualn-g scintillator

Chowdhury NNSA-SSAP Symposium Feb 21, 2018

g

• Excellentn-g pulse-shapediscrimination

•GammaresolutionbetterthanNaI

• ~10%neutronpulseheightresolution!!

• NolongToF armneeded• closeplacementincreasesgeometricalefficiency


• Eliminate6Li(n,a)thermalpeakvia7Li-enrichedC7LYC• Explorefastneutronspectroscopypotential• A16-elementarrayof1”x1”C7LYC(largestcrystalsavailableatthetime)

SCANS :SmallC7LYCArrayforNeutronSpectrocopy


• NuclearsciencewithSCANS(C7LYC)• Larger(3”x3”)crystal(acquireandcharacterize)• Elastic/inelasticneutronscatteringatLosAlamos• Beta-delayedneutronspectroscopyatCARIBU• EfficiencyandlowenergymeasurementsatUML


56Fe(n,n’)atLANSCE



En > 0.9 MeV

En > 0.0 MeV

100keV slicesonincidentneutronenergy56Fe(n,n’)atLANSCE



100keV slicesonincidentneutronenergy

En > 1.9 MeV

En > 1.0 MeV

56Fe(n,n’)atLANSCEChowdhury NNSA-SSAP Symposium Feb 21, 2018



En > 2.9 MeV

En > 2.0 MeV




En > 3.9 MeV

En > 3.0 MeV



relativecross-sections(expt 1)

presentdata(50-keVslice)witharbitrarynormalizationcomparedwithsimulations/databaseforelasticangulardistributioncross-sections)


✴SeeposterbyTristanBrownformoredetails


relativecross-sections

Ramirezetal,PRC95,064605(2017)

Elastic

Inelastic(21+)

~60mb/sratminimum

~60mb/sraverage



Efficiencyestimates&35Cl(n,p)cross-sections

LANL-ledexperiment(Jan2018)Chowdhury NNSA-SSAP Symposium Feb 21, 2018

ENDF/B-VII.0(2006) ENDF/B-VII.1(2011)

1”

MCNPX


35Cl(n,p)cross-sections

12C(n,n’) 12C(n,n’)

TOFenergyMeasuredenergy

TOFenergy

Measureden

ergy

Proposaltodirectlymeasurethe35Cl(n,p)reactioncrosssectionwiththeLENZarrayofSidetectorsandtheWNRneutronbeam

ExperimentperformedinJanuary2018


b-delayedneutrontrialsatCARIBU

GammabackgroundinCARIBUhall

PRESENT

FUTURE

(CLYCresultsinconclusive,toberepeatedinnewlow-backgroundCARIBUhall)Chowdhury NNSA-SSAP Symposium Feb 21, 2018


thefirst3”x3”C7LYC

Active volume Array X 1.7



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



C7LYCtestsatUMassLowell

✦DirectlymeasureC7LYCefficiencyataccelerator✦Mono-energeticneutronsvia7Li(p,n)7Be



UMassLowellCampus


Merrimack River

East Campus South Campus

North Campus


UMassLowellCampus



RadiationLaboratory:Facilities


5.5 MV CN singleendedVan de Graaff

1 MW research reactor

p,d,Heions;100μA DCbeam;sub-nspulsing;mono-energeticpulsedneutrons

via7Li(p,n);fast-neutron

beamlineionmicroprobe;generalpurpose

scatteringchamber

openpool;LEUfuel;3horizontalbeamports;in-coresamplelocation(~1013 n/cm2/s);graphitethermalcolumn(~106 n/cm2/s);digitalneutronradiographyhotcellwithremotemanipulators100kCi 60Cosourceforgammairradiation


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



C7LYCtestsatUML

7Li(p,n)7Be (g.s)

7Li(p,n)7Be*

Neutronspectrumfrom7Li(p,n)7Be

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


✴SeeposterbyChrisMorseformoredetails

Learning with Purpose Chowdhury NNSA-SSAP Symposium Feb 21, 2018

CLYC– intrinsicactivity

Martinezetal.,arXiv:1710.02420 [physics.ins-det]

6Li-enriched2”x2”C6LYC

SCANS- 161”x1”C7LYC

3”x3”C7LYC10-hrs

0.4alphas/s

144Nd1.83MeV?

3mBq/kg

Yttrium-Group3LanthanideandActinidecontaminantsDifferentmaterialbatchesdifferentEventualneedtospecifytolerances

Self-activityasinternalcalibration?

clean

?

Learning with Purpose Chowdhury NNSA-SSAP Symposium Apr 13, 2017

machinelearningn-g discrimination

• Interconnectedlayersof“artificialneurons”• n/γ discriminationabinaryclassificationproblem• Tracepresentedtonetworkasinputs,passedthroughasinglehiddenlayerbeforereachingoutputstage

✴SeeposterbyEmeryDoucetformoredetails


A.J. MitchellPost-doc(2013-15)Currently research

fellow ANU, Canberra

Emily JacksonPh.D. 2015

Post-doc NRL (2015-17),

Currently at Andrews AFB

Nathan D’OlympiaPh.D. 2014 Currently

Senior Scientist, Passport Systems

Patrick CoppDOE SCGSR

scholar (2016)

UML PhD Student

Tristan BrownBS 2016

LANL intern(2016)

UML PhD student

Gemma Wilson

Post-doc(2015-17)Currently

post-doc at LSU/ANL

Emery DoucetBS 2016

NEUP scholar (2015)

UML PhD student

Chowdhury NNSA-SSAP Symposium Apr 13, 2017

CLYC-ers:UMassLowellstudents/postdocs

EdwardLamere

Post-doc(to start

Mar 2018)

Chris Morse

Post-doc(2015-18)

Posterpresenters


• LANL(n,n’)proof-of-principleanalysisasuccess• EfficiencyandlowenergyresponseatUMLVandeGraaff• 35Cl(n,p)cross-sectionsatLANLforsimulations• Beta-delayedneutronsatnewCARIBUhall• Intrinsicactivitymeasurements• Machinelearningn-g discrimination• NewDAQimplementedwithonlinediagnostics• Optimizen-g coincidenceswitharray• AuxiliarydetectorcandidateforFRIBdecaystation?

Summary



UMassLowellTristanBrown,EmeryDoucet,ChrisMorse,KimLister,GemmaWilson,AndrewRogers,NathanD’Olympia,

AlanMitchell,EmilyJackson,PeterBender

LosAlamosMattDevlin,JaimeGomez,Shea Mosby,RonNelson

SupportedbyU.S.DepartmentofEnergyNNSA-SSAPGrantDE-NA0002932 and

OfficeofScienceGrantDE-FG02-94ER40848

THANKYOU!

Collaborators


nuclear science with a c lyc array - orau.gov · learning with purpose cs 2 liycl 6 (clyc): novel...

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