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arXiv · 1110.3833

Pion photoproduction in a dynamical coupled-channels model

F. Huang·M. Döring·H. Haberzettl·J. Haidenbauer·C. Hanhart·S. Krewald·U. -G. Meißner·K. Nakayama
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Abstract

The charged and neutral pion photoproduction reactions are investigated in a dynamical coupled-channels approach based on the formulation of Haberzettl, Huang, and Nakayama [Phys. Rev. C 83, 065502 (2011)]. The hadronic final-state interaction is provided by the Juelich pi-N model, which includes the channels pi-N and eta-N comprising stable hadrons as well as the effective pi-pi-N channels pi-Delta, sigma-N, and rho-N. This hadronic model has been quite successful in describing pi-N to pi-N scattering for center-of-mass energies up to 1.9 GeV. By construction, the full pion photoproduction current satisfies the generalized Ward-Takahashi identity and thus is gauge invariant as a matter of course. The calculated differential cross sections and photon spin asymmetries up to 1.65 GeV center-of-mass energy for the reactions gamma p to pi+ n, gamma p to pi0 p, gamma n to pi- p and gamma n to pi0 n are in good agreement with the experimental data.

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F. Huang, M. Döring, H. Haberzettl, J. Haidenbauer, C. Hanhart, S. Krewald, U. -G. Meißner, K. Nakayama. 2011-10-17. Pion photoproduction in a dynamical coupled-channels model. https://doi.org/10.1103/physrevc.85.054003

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