Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Heidi Schuldes Heidi Schuldes for HADES the HADES Collaboration for the Collaboration Heidelberg DPGDPG Heidelberg 20152015 Outline Outline ● ● Introduction Introduction StrangenessProduction atLowEnergies Differential analysis & preliminary results of single particles Differential analysis & preliminary results of single particles in m in -y m ● Strangeness production at SIS18 energies Strangeness production at SIS18 energies ● HADES HADES ● ● ● ● ● ● ● ● + K K K- ● K ● Φ-reconstruction Φ-reconstruction + ● ● Summary Summary HeidiSchuldes t Outline § Introduction § Microscopicdescriptionofsub-threshold strangenessproduction(K0 andL) § Deepsub-thresholdstrangenessproduction (K- andφ) § Theglobalpicture § Summary ExperimentsatSIS18 DetailedStudyofMatterPropertiesatHighestμB KaoS FOPI Nucl.Phys.A931(2014) HADES ©Hossan § § § § Heavy-ionbeamsfromSIS18:Ekin =1-2A GeV Largestoppingandlongpenetrationtimes Baryondominatedsystem Highdensitiesandmoderatetemperaturesatfreeze-out Producedmattercharacterizedbyglobalproperties? 3 StrangenessProductionatSISEnergies Sub-thresholdStrangenessProduction K0S CentralAu+Au /Pb+Pb CentralAu+Au /Pb+Pb SIS18 SIS18 Datacompilation:Prog.Part.Nucl.Phys.66(2011)834-879 § Allstrangehadronsproducedbelow/closetoNN-thresholds § Steepexcitationfunctionatlowenergies § LowerproductionyieldofK- (twoordersofmagnitudew.r.t.K+) 4 Heidi Schuldes for the HADES Collaboration MicroscopicDescription DPG Heidelberg 2015 K0S ProductionComparedtoTransportModelCalculations [email protected] GeV Outline Introduction ● ● ● ● Strangeness production at SIS18 energies HADES Differential analysis & preliminary results of single particles in mt-y K+ ● PRELIMINARY K● Φ-reconstruction ● ● K0S Summary § State-of-the-arttransportmodelcalculationsoverestimateyieldand <Apart>dependenceisnotreproduced HSD v711n: Phys rep, 308:65–233, January 1999 IQMD c8: Eur.Phys.J.,A1:151–169, 1998 UrQMD 3.4: Prog.Part.Nucl.Phys., 41:255–369, 1998 5 Heidi Schuldes for the HADES Collaboration MicroscopicDescription DPG Heidelberg 2015 K0S ProductionComparedtoTransportModelCalculations [email protected] GeV Outline Introduction ● ● ● ● Strangeness production at SIS18 energies HADES Differential analysis & preliminary results of single particles in mt-y K+ ● PRELIMINARY K● Φ-reconstruction ● ● K0S Summary § InclusionofrepulsiveKNpotentialreducesyieldand<Apart> dependence HSD v711n: Phys rep, 308:65–233, January 1999 IQMD c8: Eur.Phys.J.,A1:151–169, 1998 UrQMD 3.4: Prog.Part.Nucl.Phys., 41:255–369, 1998 6 Heidi Schuldes for the HADES Collaboration MicroscopicDescription DPG Heidelberg 2015 Pt DistributionofK0S andL ComparedtoTransportModelCalculations [email protected] GeV Outline Introduction ● ● (normalization:600<pt <900MeV/c) ● ● K0S Strangeness production at SIS18 energies HADES (normalization:700<pt <1000MeV/c) Differential analysis & preliminary results of single particles in mt-y ● ● ● ● K+ KΦ-reconstruction Summary PRELIMINARY PRELIMINARY § Modelsw/opotentialdonotmatchlowpt 7 Heidi Schuldes for the HADES Collaboration MicroscopicDescription DPG Heidelberg 2015 Pt DistributionofK0S andL ComparedtoTransportModelCalculations [email protected] GeV Outline Introduction ● ● (normalization:600<pt <900MeV/c) ● ● K0S Strangeness production at SIS18 energies HADES (normalization:700<pt <1000MeV/c) Differential analysis & preliminary results of single particles in mt-y ● ● ● ● K+ KΦ-reconstruction Summary PRELIMINARY PRELIMINARY § Modelsw/opotentialdonotmatchlowpt § BetterdescriptionofkaonspectrawithKNpotential(noeffectforL) 8 Heidi Schuldes for the HADES Collaboration MicroscopicDescription DPG Heidelberg 2015 Pt DistributionofK0S andL ComparedtoTransportModelCalculations [email protected] GeV Outline Introduction ● ● (normalization:600<pt <900MeV/c) ● ● K0S Strangeness production at SIS18 energies HADES (normalization:700<pt <1000MeV/c) Differential analysis & preliminary results of single particles in mt-y ● ● ● ● K+ KΦ-reconstruction Summary PRELIMINARY PRELIMINARY § § § Ø Modelsw/opotentialdonotmatchlowpt BetterdescriptionofkaonspectrawithKNpotential(noeffectforL) L pt spectrumbestdescribedbyUrQMD NomodeldescribessimultaneouslykaonandL results 9 DeepSub-thresholdStrangenessProduction K- /K+ Production- ComparisontoKaoS PRELIMINARY PRELIMINARY § NostrongcentralitydependenceofK- /K+ ratio 10 DeepSub-thresholdStrangenessProduction K- /K+ Production- ComparisontoKaoS *40%mostcentral PRELIMINARY PRELIMINARY PRELIMINARY KaoS:Phys.Rev.C75:024906,2007 § NostrongcentralitydependenceofK- /K+ ratio § EffectivetemperatureofK- systematicallybelowK+ 11 DeepSub-thresholdStrangenessProduction K- /K+ Production- ComparisontoKaoS *40%mostcentral PRELIMINARY PRELIMINARY PRELIMINARY KaoS:Phys.Rev.C75:024906,2007 § NostrongcentralitydependenceofK- /K+ ratio § EffectivetemperatureofK- systematicallybelowK+ Ø Interpretation:Productioncoupledviastrangeness exchangereaction+laterfreeze-outofKPhys.Rept.510(2012)119-200 12 DeepSub-thresholdStrangenessProduction φ MesonastheGameChanger Compilationofdata:: Prog.Part.Nucl.Phys.66(2011)834-879 § Constantφ /K- ratioathighenergies 13 DeepSub-thresholdStrangenessProduction φ MesonastheGameChanger PRELIMINARY HADESAr+KCl Phys.Rev C80(2009)025209 FOPINi+Ni Nucl.Phys.A714(2003)89-123 FOPIAl+Al arXiv:1512.06988 § Enhancedφ /K- ratioatenergiesbelowNN-thresholdinsmallsystems 14 DeepSub-thresholdStrangenessProduction φ MesonastheGameChanger BR(φ ->K+K- )=48.9% PRELIMINARY * *40%mostcentral Compilationofdata:: Prog.Part.Nucl.Phys.66(2011)834-879 § Au+Au @√𝑠 =2.41GeV:φ/K- =0.52± 0.16 Ø ~25%ofallmeasuredK- fromφ feed-down(andnotfroms-exchange) Ø φ importantsourceforK- productionbelowNN-threshold 15 Heidi Schuldes for the HADES Collaboration DeepSub-thresholdStrangenessProduction φ MesonsasSourceofK- DPG Heidelberg 2015 [email protected] GeV Outline Introduction ● ● ● ● Strangeness production at SIS18 energies HADES PRELIMINARY Differential analysis & preliminary results of single particles in mt-y ● ● ● ● K+ KΦ-reconstruction Summary § Feed-downcontributionfromφ decayscanexplainlowerinverseslope parameterofK- T(K-)=84± 6MeVincomparisontoK+ T(K+)=104± 2MeV § Measuredrapiditydistributionreproducedbycocktail Ø Noindicationforsequentialkaonfreeze-out 16 DeepSub-thresholdStrangenessProduction φ MesonsasSourceofKFOPI:Eur.Phys.J.A52(2016)no.6,177 no feed-down correction K- feed-down corrected § Feed-downcontributionfromφ decayschangesconclusiononkaon potential 17 Heidi Schuldes for the HADES Collaboration StrangenessProduction:TheGlobalPicture <Apart>DependenceofMultiplicities DPG Heidelberg 2015 [email protected] GeV Outline Introduction ● ● ● PRELIMINARY PRELIMINARY ● Strangeness production at SIS18 energies HADES Differential analysis & preliminary results of single particles in mt-y § Samedependenceonnumberof participatingnucleons: Summary M𝑢𝑙𝑡~<Apart>α:α=1.35± 0.07 ● ● ● ● K+ KΦ-reconstruction § NotexpectedfromdifferentNNthresholds 18 StrangenessProduction:TheGlobalPicture <Apart>DependenceofMultiplicities Charged Kaon- & φ-Reconstruction in Au+Au @ 1.23 AGeV KaoS [email protected] GeV Heidi Schuldes for the HADES Collaboration DPG Heidelberg 2015 PRELIMINARY Outline Introduction ● ● ● ● Strangeness production at SIS18 energies HADES Differential analysis & preliminary results of single particles in mt-y ● ● ● ● + K KΦ-reconstruction Summary § Samedependenceonnumber ofparticipatingnucleons: M𝑢𝑙𝑡~<Apart>α:α=1.35± 0.07 § Notexpectedfromdifferent NN-thresholds Ni+Ni/Al+Al ≈1.9A GeV § Sameobservationathigher energiesandsmallercollision systems(αK+=1.34± 0.16, αK-=1.22± 0.27,constantφ/K-) KaoS:Phys.Rev.C75:024906,2007 FOPI:Phys.Rev.C94(2016)no.1,014901 19 Heidi Schuldes for the HADES Collaboration StrangenessProduction:TheGlobalPicture <Apart>DependenceofMultiplicities DPG Heidelberg 2015 [email protected] GeV Outline Introduction ● ● ● PRELIMINARY PRELIMINARY ● Strangeness production at SIS18 energies HADES Differential analysis & preliminary results of single particles in mt-y § Samedependenceonnumberof participatingnucleons: Summary M𝑢𝑙𝑡~<Apart>α:α=1.35± 0.07 ● ● ● ● K+ KΦ-reconstruction § NotexpectedfromdifferentNNthresholds Ø Universalcentralitydependence ofstrangenessproduction § Cansystembetreated macroscopically? 20 Heidi Schuldes for the HADES Collaboration ChemicalFreeze-Out StatisticalHadronization Model DPG Heidelberg 2015 [email protected] GeV Outline Introduction ● ● ● ● Strangeness production at SIS18 energies HADES Differential analysis & preliminary results of single particles in mt-y ● ● ● ● K+ KΦ-reconstruction Summary PRELIMINARY *20%mostcentral § HadronyieldswelldescribedbySHMwithglobalparameters:T,μB,RV,RC THERMUSv2.3 Comput.Phys.Commun.180:84-106,2009 21 Heidi Schuldes for the HADES Collaboration ChemicalFreeze-Out StatisticalHadronization Model DPG Heidelberg 2015 [email protected] GeV Outline Introduction ● ● ● ● Strangeness production at SIS18 energies HADES Differential analysis & preliminary results of single particles in mt-y ● ● ● ● K+ KΦ-reconstruction Summary PRELIMINARY *20%mostcentral *40%mostcentral § HadronyieldswelldescribedbySHMwithglobalparameters:T,μB,RV,RC § Strangenesscanonicallysuppressed φ /K- ratio THERMUSv2.3 Comput.Phys.Commun.180:84-106,2009 22 Heidi Schuldes for the HADES Collaboration ChemicalFreeze-Out StatisticalHadronization Model DPG Heidelberg 2015 [email protected] GeV Outline Introduction ● ● ● ● Strangeness production at SIS18 energies HADES Differential analysis & preliminary results of single particles in mt-y ● ● ● ● K+ KΦ-reconstruction Summary PRELIMINARY *20%mostcentral § § § § HadronyieldswelldescribedbySHMwithglobalparameters:T,μB,R,RC Strangenesscanonicallysuppressed φ /K- ratio T,μB higherthanexpected Moreparticlespeciesincluded Radiuslowerthanexpected Eigenvolumes 23 Heidi Schuldes for the HADES Collaboration CascadeProductionPuzzle DPG Heidelberg 2015 Xi- Enhancement Outline Introduction ● Eur.Phys.J. A47 (2011) 21 ● ● ● Strangeness production at SIS18 energies PRL 114 (2015) 212301 HADES Differential analysis & preliminary results of single particles in mt-y ● ● ● ● p+Nb K+ KΦ-reconstruction Summary Ar+KCl SHM @1.76AGeV PRELIMINARY § StrongexcessofX§ Alreadypresentincoldnuclearmatter 24 Heidi Schuldes for the HADES Collaboration KineticFreeze-Out SimultaneousBlastWaveFit DPG Heidelberg 2015 [email protected] GeV Outline Introduction ● ● ● PRELIMINARY ● Strangeness production at SIS18 energies HADES Phys.Rev.C48,2462 Differential analysis & preliminary results of single particles in mt-y ● ● ● ● § Blastwavemodel: K+ KΦ-reconstruction Summary Linearflowvelocityprofile: § Proton,KaonandPionspectra welldescribedbysimultaneous blastwavefitwithglobal parameters: *Fatpointsincludedinfit *0-10%mostcentral,syserrondiffcountrate5% j:0-20%mostcentral,syserrondiff.countrate10% 28 Freeze-OutParameter ComparisontoWorldData #0-20%mostcentral STARarXiv:1701.07065,2016 *0-10%mostcentral # * * § Globalfreeze-outparametersfitwellintotrendofworlddata 26 Summary Microscopicdescription: § KaonspectrabestdescribedbyIQMDwithpotential, however,doesnotdescribeL spectra Ø Nomodeldescribesallparticlespeciessimultaneously Deepsub-thresholdstrangenessproduction: § φ sizeablesourceforK- production § Feed-downcanexplainlowereffectivetemperature andrapidityspectrumofKØ Noindicationforsequentialfreeze-outofK+/KTheglobalpicture: § Universalcentralitydependenceofstrangeness production § SHMdescribesparticleyields(exceptX-) K0S PRELIMINARY PRELIMINARY PRELIMINARY BACKUP 28 φ /K- ratio Excitationfunction PRELIMINARY UrQMD tuned:J.Phys.G43(2016)1,015104 HADESAr+KCl Phys.Rev C80(2009)025209 FOPINi+Ni Nucl.Phys.A714(2003)89-123 FOPIAl+Al arXiv:1512.06988 Compilationdatahigherenergies: Prog.Part.Nucl.Phys.66(2011)834-879 § Ø Ø Ø φ/K- =0.52± 0.16 ~26%ofallmeasuredK- fromφ feed-down TrendexpectedfromSHMwhenopenstrangenesssuppressedbyRC Firsttransportmodeltodescribedata:UrQMD (tuned)whenincludingnew decaychannelsfromhighmassbaryonicresonances 29 K+ vs.Transport 30 K+ vs.Transport 31 StrangenessProductionatSISEnergies Xiupperlimit 32 BlastWaveFit Systematicerrorinvestigation *0-10%mostcentral § Variationofparticlespeciesincludedinsimultaneousfit § Strongesteffectifprotonsorboth,p+ andp-, areexcludedfromfit Ø Conservativeerrorstillspectrapublished 33 BlastWaveFit Centralitydependence *onlystatisticalerrors § Slightlylowerkineticfreeze-outparametersformoreperipheralcollisions 34 BlastWaveFit Centralitydependence STARarXiv:1701.07065,2016 *onlystatisticalerrors § Slightlylowerkineticfreeze-outparametersformoreperipheralcollisions § Differentbehaviorathigherenergies 35 Chemicalvs.KineticFreeze-out § Tchem consistentwithTkin obtainedfromblastwavefittotransverse massspectraofhadronsandfromextrapolationofmassdependence ofeffectivetemperatures 36 StrangenessProductionatSISEnergies Xiupperlimit 37 StrangenessProductionatSISEnergies Kaonflow 38 K- /K+ ratio CentralitydependenceandcomparisontoKaoS * * 0-40%mostcentral PRELIMINARY PRELIMINARY § NostrongcentralitydependenceofK- /K+ ratioobserved § K- /K+ ratiofitsenergydependenceofKaoS data 39 Multidifferentialanalysisofpions andprotons Highstatistics(1outof30days) ππPRELIMINARY p PRELIMINARY PRELIMINARY 40 φ /K- ratio Centralitydependence § φ/K- ratioalmostconstantasfunctionofcentrality § SimilartrendobservedfromFOPIforNi+Ni @1.9AGeV 41 Centrality 42 K+Production Centralitydependent 43 Efficiency*acceptance K- K+ φ 44 Efficiency*acceptance 45 Invariantmassφ 46 HADESPerformance Au+Au at√𝑠 =2.41GeV Highinteractionrates § Beam:1.5x106 Auions/s § Triggerratesupto8kHz Centralitydependence § 40%mostcentralcollisions § 2.1x109 eventsanalyzed CBMcollab arXiv:1607.01487[nucl-ex] 5 HADESPerformance Au+Au at1.23AGeV ExcellentParticleIdentification 48 HADESPerformance ReconstructionofStrangeHadronsinAu+Au at√𝑠 =2.41GeV LargeAcceptance *40%mostcentral K0S K0S Ø 4πMultiplicities Extrapolationinmt: 7 Reconstructionofφ Mesons BR(φ ->K+K- )=48.9% MEbackground * Notused for signal extraction! *40%mostcentral § Firstmeasurement of f mesons sofar below NN-threshold § Intotalabout 1000f reconstructed Ø Multi-differentialanalysis possible 50