Extractionofresonanceparametersfrommesonnstar共振参数提取的介子学习教案

1、会计学1Extractionofresonanceparametersfrommesonnstar共振参数共振参数(cnsh)提取的提取的介子介子第一页，共15页。Excited baryon resonance in N, *N reactions Structure of resonance : mass, form factor, branching ratio第1页/共15页第二页，共15页。Mass, Width,ElectromagneticN-N* form factorsLattice QCDHadron ModelsDynamical Coupled-Channels Ana

2、lysis EBACReaction Data第2页/共15页第三页，共15页。Resonances: poles of the scattering amplitudescharacterize resonances Pole position mass, width Residue Form factorsForm Factor第3页/共15页第四页，共15页。N*NVPI/GWBW,Pole(AC)BWCMB,Pitt-ANLBW,Pole(AC)Bonn-GatchinaBW,Pole(AC)BW,Pole(AC)GiessenBW,Pole(SP)BWJlab/YerevanBWMA

3、IDBWDMTBW,Pole(SP)JuelichPole(AC)EBACPole(AC)BW,Pole(AC)Extraction of Resonance ParametersBW Breit-Wigner, SP speed-plot, AC Analytic continuation Dynamical model第4页/共15页第五页，共15页。Dynamical Model of meson production reactionCoupled channels model with N three-body unitarityG0(W): MB Green function N*

4、 Green function: mass N* vertex : form factor 第5页/共15页第六页，共15页。Resonance Pole on unphysical sheetIm WRe WScatteringPhysical SheetBound stateResonanceUn-physical sheetNeed to examine T(W) for complex W, un-physical sheetMulti-sheets for coupled channel Ex: 2ch pp uu up pu (Kato 65,.) Resonance第6页/共15

5、页第七页，共15页。Analytic continuation of T(W) T(W) : obtained by solving Lippman-Schwinger EquationlChoose appropriate path for phys/un-phys sheets (Pearce-Gibson 89)lV(p,p) must be analytic in the region of path deformation=W-planeRe WIm WRe pExample: T for un-physical sheet above thresholdp-planeIm p第7页

6、/共15页第八页，共15页。Green functions with unstable particleW-planeExample: for un-phys and p-plane(Pearce Afnan 84)第8页/共15页第九页，共15页。Toy model N* couple with only S-wave, non-rela : analytic solution第9页/共15页第十页，共15页。P33Im WRe WResults from EBAC model (preliminary)Contour plot of |T(W)|MwidthRphiArndt0612119

7、952-47Hoehler93120910050-48Cutkosly80121010053-47Doring0912189047-37第10页/共15页第十一页，共15页。P11Pole trajectory123Multi-poles associated with single resonancein coupled channelpreliminarypolesours1357 - i 761364 - i 105R. A. Arndt et al. 1359 - i 821388 - i 83M. Doring et al.1387 - i 147/21387 - i 71第11页/

8、共15页第十二页，共15页。Pole of T matrix gives resonance information Mass and width from pole position, form factors from residueA method to extract resonance parameters using analytic continuation of the scattering amplitude is developed.Applied for N scattering amplitude of EBAC current model P33, P11 resonance poles are extractedExtracting resonance form factor is in progress.第12页/共15页第十三页，共15页。Resonance MassResonance Form Factor (complex number)第13页/共15页第十四页，共15页。PDG 08: BW and Pole Example P11BWPoleArnt06 (AC)1485 284i/21354 162i/2Cutkosky80(AC)1440 340i/21375 180i/2Vrana00 (AC)1479 490i/21