Extractionofresonanceparametersfrommesonnstar共振参数提取的介子

motivationdynamicalmodelofmesonproductionreactionextractionofresonanceparameters,(analyticcontinuationofscatteringamplitudes)P33andP11fromcurrentEBACmodelsummary

Excitedbaryon

resonanceinπN,γ*NreactionsStructureofresonance:mass,formfactor,branchingratioMass,Width,ElectromagneticN-N*formfactorsQCDLatticeQCDHadronModelsDynamicalCoupled-ChannelsAnalysis@EBACReactionDataResonanceResonances:polesofthescatteringamplitudescharacterizeresonances

Poleposition

mass,width

Residue

FormfactorsFormFactorπNγ*NVPI/GWBW,Pole(AC)BWCMB,Pitt-ANLBW,Pole(AC)Bonn-GatchinaBW,Pole(AC)BW,Pole(AC)GiessenBW,Pole(SP)BWJlab/YerevanBWMAIDBWDMTBW,Pole(SP)JuelichPole(AC)EBACPole(AC)BW,Pole(AC)ExtractionofResonanceParametersBWBreit-Wigner,SPspeed-plot,ACAnalyticcontinuationDynamicalmodelDynamicalModelofmesonproductionreactionCoupledchannelsmodelwithππNthree-bodyunitarityG0(W):MBGreenfunctionN*Greenfunction:massN*vertex:formfactor

ResonancePoleonunphysicalsheetImWReWScatteringPhysicalSheetBoundstateResonanceUn-physicalsheetNeedtoexamineT(W)forcomplexW,un-physicalsheetMulti-sheetsforcoupledchannelEx:2chppuuuppu(Kato65,..)ResonanceAnalyticcontinuationofT(W)T(W):obtainedbysolvingLippman-SchwingerEquationChooseappropriatepathforphys/un-physsheets(Pearce-Gibson‘89)V(p’,p)mustbeanalyticintheregionofpathdeformation=W-planeReWImWRepExample:Tforun-physicalsheetabovethresholdp-planeImpGreenfunctionswithunstableparticleW-planeExample:forun-physandp-plane(PearceAfnan‘84)ToymodelN*couplewithonlyπΔS-wave,non-rela:‘analytic’solutionP33ImWReWResultsfromEBACmodel(preliminary)Contourplotof|T(W)|MwidthRphiArndt0612119952-47Hoehler93120910050-48Cutkosly80121010053-47Doring0912189047-37P11Poletrajectory123Multi-polesassociatedwithsingleresonanceincoupledchannelpreliminarypolesours1357-i761364-i105R.A.Arndtetal.1359-i821388-i83M.Doringetal.1387-i147/21387-i71SummaryPoleofTmatrixgivesresonanceinformationMassandwidthfrompoleposition,formfactorsfromresidueAmethodtoextractresonanceparametersusinganalyticcontinuationofthescatteringamplitudeisdeveloped.AppliedforπNscatteringamplitudeofEBACcurrentmodelP33,P11resonancepo