Meson Production reaction on the N* resonance region

T. Sato(Osaka Univ.)

Dec 2007 KEK

Motivation

Dynamical model of meson production reaction

Results

summary

Particle LIJ Particle LIJ N(1440) P11 **** **** *** D(1232) P33 **** **** ***N(1520) D13 **** **** **** D(1600) P33 *** *** **N(1535) S11 **** **** *** D(1620) S31 **** **** *** N(1650) S11 **** **** *** D(1700) D33 **** **** ***N(1675) D15 **** **** **** D(1750) P31 * * -N(1680) F15 **** **** **** D(1900) S31 ** ** *N(1700) D13 ** *** ** D(1905) F35 **** **** *N(1710) P11 *** *** *** D(1910) P31 *** *** *N(1720) P13 **** **** ** D(1920) P33 *** *** *N(1900) P13 ** ** - D(1930) D35 *** *** **N(1990) F17 ** ** * D(1940) D33 * * -N(2000) F15 ** ** - D(1950) F37 **** **** ****

Nucleon resonances

“The status of the one- and two-star states found in KH80 and CMB80 fits is now doubtful” PDG

Objective of our study :

Extract N* and Delta properties from meson production reaction

Interpret resonance parameters

W<1.7GeV structure of ‘established’ resonances

N(1535), N(1440)

W>1.7GeV establish /discover nucleon resonances

High precision data of electromagnetic meson production reaction Jlab, Bonn, Spring8, Mainz

photo meson production reaction

Coupled-channel analysis of meson production reaction

differential cross section, polarization,..

amplitudes

Resonance parameters

Neutrino reaction in the resonance region

H.Gallagher, nucl. Phys. Proc B112/Kitagaki et al. PRD34

Single pion productionPi-N invariant mass distribution

One and Two pion production cross section

2-pi

1-pi

Nuclear effects in the N* resonance region

A

N

M. Hirata et al.PRC66 (2002)

1pi

2pi

Fermi averageSpreding potential of N*,Delta pion distortion

1pi

2pi

Dynamical model of meson production reaction

B. Julia-Diaz, T.-S. H. Lee, A. Matsuyama, L.C. Smith, T. Sato

　　　　　　　　 Phys. Rep. 439 (2007) 193 Phys. Rev. C76 (2007) 065201 arXiv 0712.2283

Effective Hamiltonian of Meson-Baryon

energy independent interaction, derived using unitary transformation method

solve coupled channel integral equation

Three body unitarity

MAID

Single pion photoproduction

Our T-matrix

K-matrix

Dynamical model

Status on the analysis of meson production reaction

Julia-Diaz, Lee, Matsuyama, Sato

Julia-Diaz, Lee, Matsuyama, Smith, Sato

Julia-Diaz, Kamano Lee, Matsuyama, Sato

Paris, Lee, Sato

Durand, Julia-Diaz, Lee, Saghai, Sato

Lee, Sibirtsev, Tsushima

Pion nucleon elastic scattering

Pion-nucleon scattering W<2GeV, S,P,D,F waves

One N*( two N* for P33,P11,S11,D13)

Coupling constants, form factors fitting SAID of GWU/VPI

Refine parameters by comparing cross section data

Total cross section

I=1/2

I=3/2

Re Im

Pion photoproduction

Vary bare gN-N* amplitudes fitting data (total, differential cross section W<1.52GeV)

Coupled channel effects on differential cross section

Polarization (beam asymmetry)

Resonance parameters

Meson cloud effects on gNN* form factors

Meson-cloud effects on resonance vertex

r<R LQCDr>R Meson-Baryon reaction

Probe N* using meson-baryon

SUMMARY

Sensitivity on N*symmetry: iso-spin

spin-parity

near threshold mesondynamical: higher Q2 region

non-resonant resonance