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PNU & NuRI. A new nucleon resonance. in eta photoproduction. 1 .Nuclear physics & Radiation technology Institute (NuRI), Pusan National Univ., Korea 2. Yukawa Institute for Theoretical Physics (YITP), Kyoto Univ., Japan 3 .Research Center for Nuclear Physics (RCNP), Osaka Univ., Japan.
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PNU & NuRI A new nucleon resonance in eta photoproduction 1.Nuclear physics & Radiation technology Institute (NuRI), Pusan National Univ., Korea 2. Yukawa Institute for Theoretical Physics (YITP), Kyoto Univ., Japan 3.Research Center for Nuclear Physics (RCNP), Osaka Univ., Japan
PNU & NuRI neutron proton the same value by isospin symmetry Model for κN : Chiral Quark Soliton Model :Difference from here!! Selection rule of the SU(3) flavor symmetry 8 8 10 Unique G.S.Yang et al.,Phys.Rev.D71, 094023(2005) Motivation GRAAL[hep-ex/0409032] Only for the neutron Peak appears at ~ 1675MeV Width ~ 10MeV (with Fermi motion correction)
PNU & NuRI Other results Peak structure exists! hep-ex/0703003 Tohoku LNS result GRAAL recent result
PNU & NuRI parity +, parity -, size ~0.2 for neutron ~0.0 for proton Results of spin 1/2 k.s.choi et al., Phys.lett.B636,253 No evidence of spin 1/2 for N*(1675). Check other physical observables.
PNU & NuRI Vector Meson exchange (background) 7 resonances + background !! N ( Background ) N* (resonances) (1520, 1535,1650,1675,1710,1720) +1675(new) How to describe? in region of 1.4GeV~2.0GeV Resonance of Jp=1/2±and 3/2±
PNU & NuRI Interections for backgrounds Coupling constant set V.G.J.Stoks and T.A.Rijken,Phys.Rev.C 59, 3009 (1999) L.Tiator, C.Bennhold and S.S.Kamalov, Nucl.Phys.A 580, 455 (1994) From partial decay width
PNU & NuRI Interections for resonance
PNU & NuRI Spinors for higher spin Spin3/2 Spin5/2
PNU & NuRI couplings for resonance A.I.Titov and T.-S.H.Lee Phys. Rev. c66, 015204 (2002).
PNU & NuRI Amplitudes for backgrounds
PNU & NuRI Amplitudes for resonance :The projection operators for higher spin
PNU & NuRI Parametersfor calculation Parameters of the nucleon resonance Cut off parameter :
PNU & NuRI Numerical calculation The physical observable involved N*(1675) resonance for Jp=1/2±and 3/2± Differential cross section VS. energy in 140° Beam asymmetry in 140° strangth of transition magnetic moment of N*(1675)
PNU & NuRI Differential crossection(1) Neutron case
PNU & NuRI Differential crossection(2) Proton case
PNU & NuRI Beam asymmetry(1) Neutron case
PNU & NuRI Beam asymmetry(2) Proton case
PNU & NuRI Numerical results The physical observable involved N*(1675) resonance for Jp=1/2±and 3/2± Differential cross section VS. energy in 140° proton and neutron channels are described successfully . Beam asymmetry in 140° Neutron case : good proton case : not as good as neutron strength of transition magnetic moment of N*(1675) Spin 1/2 case : around 0.1 spin 3/2 case : around 0.01~0.03.
PNU & NuRI Summary and conclusion The Born approximation and effective Lagrangian method. reproduction The GRAAL experiment with seven resonances (N*(1520),N*(1535),N*(1675), N*(1520), N*(1710),N*(1720)+N*(1675)new ) Successful description of physical observations for neutron case. Comparison between spin 1/2 and spin 3/2 results