Review of Recent and Future Needs in Hadronic Flavor Particle Production Measurements

Measurements

Dr.NickolasSolomey

IllinoisInstituteofTechnology,Chicago,USAandFermiNatinonalAcceleratorLaboratory,Batavia,Ill.USA

arXiv:hep-ex/0608038v1 14 Aug 20061Introduction

Twonewrecentlycompletedexperimentsstudyinghadronicflavorparticleproduction,HARP-PS214atCERNandMIPP-E907atFermilabhavejustcompleteddatataking.TheBNLE910experimentwhichendedsixyearsagoisstillinthedataanalysisprocess.Collectivelytheseexperimentscover1to120GeV/conmultipletargets(liquidHydrogen,K2KandMinostargetsandvariousnucleartargetsincludingUranium)forsixbeamspecies(pion,kaon,protonsandtheirantiparticles).Theyexpandupontheoldercrosssectiondataandbringavarietyofnewphysicsgoals:improvedhadronicflavorpro-ductioncrosssections,studyingfundamentalscalinglawrelationships[1]andnucleartargetproductionstudies.Figure1showsthelargeuncertaintyusingcurrentproductioncross-sectiondatawithasimulatedneutrinotargetfortheFermilabMiniBooNEexperiment[2].Thisandotherneutrinoproductionex-perimentsneedsubstantialimprovements,sincethisiswhatcurrentlylimitsadvancesinneutrinophysics.

PreprintsubmittedtoElsevierScience

7February2008

Fig.1.CalculatedneutrinofluxesfromasimulatedMiniBooNEtargetusingvariouscodesanddifferentmeasurements.

Inthesenewexperimentsparticletrackingandidentificationarebothparamount,bringingessentialinformation,seefigures2and3.Thesenewdatasetandthebroadphysicsanalysisplannedwithpreliminaryfirstresultsonallofthesetopicsarepresentedinthenextsection.

TheproposedfuturerunofanupgradedMIPPdetectorisofimportancetofutureneutrinophysicsprogramsworldwide,suchasIce-Cube,NOνA,PierreAugerandSuperK/HyperKexperiments.Bydoingahighstatisticsrunin-cludingLiquidNitrogen,forthecompleteforwardproductionhemispherewiththreesigmaparticleidentification,itwillpermitdetailedcrosssectionmea-surementstorefinetheMonte-CarlogeneratorssuchasFlukaorMARS,whichareofmajorrelevanceforimprovingthesefutureneutrinodetectors.CurrentSuperKatmosphericneutrinosresultsarelimitedtoa20%error[3]fromtheseuncertaintieswhiletheIce-Cubeexperimentseesa30to40%[4]impactusingthecurrentknowncross-sections.

2Recentresults

NewresultswerereportedbytheBrookhavenNationalLaboratoryE910ex-perimentwithinthelasttwoyearswith6.4and12.3GeV/cprotonsona

2

Fig.2.MomentumresolutionfromtheHarpexperiment(top)circleareMCandpointsfordata,andanexampleevent(bottom)fromtheMIPPexperimentshowingvertexingandhighdensitytrackingabilitiesoftheTPC.

Berylliumtarget[5].ThemostrecentpublishedcrosssectionresultscomefromtheHarp(CERNPS214)experiment.Theyreportedtwomeasurementsof12.9GeV/cprotononAluminum[6]ofinteresttotheJapaneseK2Kex-perimentand8.9GeV/cprotonsonBeryllium[7]whichisofinteresttotheFermilabMiniBooNEexperiment.

NuMITargetStudiesfortheMINOSExperimentwiththeMIPPdataarewelladvanced.CrucialπandKproductionstudiesthattheMINOSanalysiswilleventuallyrelyuponwillbeprovidedbytheMIPPexperimentusingthespareNuMIcompositetarget.A120GeV/cbeamofpureprotonsidenticaltothatwhichhitstheNuMIhorntargetwasrunintheMIPPexperimentfortwomonthsandcollected2millionevents.Theseeventsusingthepro-3

Fig.3.TwoexamplesoftheparticleidentificationinthesemeasurementsaretheE910TPCusingdE/dxontheleft(thisisthesameTPCthatiscurrentlyintheFermilabMIPPexperiment)andontherightistheMIPPRICHdetector.

jectileparticletrackingandsecondaryparticleproductionidentificationandmomentumreconstructionshowfirstresultsfromthisanalysisinfigure4[8].TheMIPPexperimentisalsostudyingparticleproductionmultiplicitiesanditsAdependence,seefigure5,forthefirsttentativeresultswhichareinagreementwith[9].

3Futureimprovedmeasurements

TheFermilabMIPPexperimentproposestohaveanupgradedrunfrom2007to2009withafasterreadoutoftheTPCsothata3kHzratecanbeachieved,4πacceptancebyinstallingabackwardhemispheredetector,anewsiliconvertex-interactiontrigger,animprovedcalorimeterswhichisacooperationwiththeInternationalLinearColliderandotherminorbutessentialmodifi-cations.

AnextensiverunwithaLiquidNitrogentargetwithalargedatasamplesothatfinesegmentationinanglecanbemeasuredforallinteractionspecies,thisisexplicitlyneededfortheatmosphericneutrinoexperimentssuchas:Ice-CubeandHyper-K,toimprovetheirneutrinofluxfromπandKdecays.Figure6showsthecurrentlimitationtothesmallAmandaexperimentabove4GeV/c,thiscomesfromtheCosmicRayuncertaintiesofatmosphericpro-ductionofKaonsandpions[10].Currentmodelsareuncertainabove5GeV/c.MembersoftheIce-CubeexperimentfromtheUniv.ofWisconsinandFer-milabmembersofthePierreAugerExperimentwillbejoiningtheMIPPupgradedexperiment.Itplanstostudydifferentelementsforimprovements

4

Fig.4.Preliminarystudyofπ(top)andK(bottom)productionby120GeV/cprotonbeamontheNuMItargetintheMIPPexperiment.

tohadronicshowersimulationcodeforhadroniccalorimeterdesign.ThesemeasurementsarevitaltoimprovingHadronCalorimetry,whichisthemostimportant√detectorintheILC.Seefigure7whichshowsthedifferencebetweena60%/Eresolution,acrucialnecessitytoseparatingthetwojetbackgroundfromWandZ.

HadronCalorimetrydesignsrelyuponMonte-Carlocodeswherethedetectormaterialsarenotwellknown.TheupgradedMIPPexperimentwillstudy40nucleifrom1to100GeV/c.TheresponseoftheILCtestcalorimetertoneutronsanditsefficiencyisessentialtotheParticleFlowalgorithms.ByputtingtheILChadroncalorimeterintheMIPPbeamlinetheywillbeabletoprovideadirectmeasureofneutronenergyandefficiencyresponsewithtaggedneutrons[11].ItwillalsoprovideauniqueopportunityfortaggedK0

¯0physicsprogram.andK

5

Fig.5.PreliminaryMIPPresultsonthechargedparticlemultiplicityfrom0.15to1.0GeV/cparticlesforbeamparticlesat+58GeV/cwithtaggedπ,KandprotonsonnucleartargetsfromA=1hydrogentoA=206Bismuth,thedatahasbeencorrectedforemptytargetruns.

4Conclusion

TheE910,MIPPandHarpexperimentswithcurrentimprovementstothehadronicflavorproductionstudieshasgreatlyhelpedmakeimprovedcross-sections.FuturedatafromtheupgradedMIPPexperimentwillbeaguidinglightforbothatmosphericandacceleratorbasedneutrinoexperiments,with-outwhichthereislittleornoreasontocontinueneutrinostudies.Agreatim-provementinanti-protoninteractionsandcharmproductionisalsoplanned.Futuredataandanalyzedresultsareexcitinglyawaited.

References

[1]R.Rajaetal.,Phys.Rev.D,v18,p204,1978.

[2]D.Schmitz,ConstrainingMiniBooNENeutrinoFluxPredictionswiththe

HARPExperiment,APSmeetingApril2005.[3]Y.SuzukifortheSuperKcollaboration,privatecommunications,March2006.[4]F.HalzenfortheIce-Cubecollaboration,privatecommunications,March2006.

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Fig.6.ErrorsinatmosphericneutrinoproductionbaseduponcurrentNitrogenkaonproductioncross-section.

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Fig.7.Hadroniccalorimeterenergyresolutionat60%/(right)forthesumoftwojetsonthexandyaxis.

E

[5]B.ColeandR.SoltzfortheE910collaboration,privatecommunications,June

2006.[6]M.G.Catanesietal.(Harpcollaboration),Nucl.Phys.B,v732,pages1-45,

2006.[7]M.G.Catanesietal.(Harpcollaboration),Aprecisionmeasurementofthe

7

double-differentialproductioncross-section,d2σπ/dpdΩ,forpionsofpositivecharge,hep-ex/0510039

[8]J.Paley(fortheMIPPcollaboration),Hadroniccrosssectionsforneutrino

productioninMIPP,APS2006posterpresentation.[9]F.M.Liuetal.Phys.Rev.C69,0002(2004).

[10]T.Montaruli,Univ.ofWisconsinfortheIce-Cubecollaboration,private

communications,March2006.[11]R.Rajaetal.,Taggedneutrons,anti-neutronandK-longbeamintheupgraded

MIPPexperiment,MIPPnote130,23May2006.

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