Backward pion photoproduction
Abstract
We present a systematic analysis of backward pion photoproduction for the reactions gamma p -> pi0 p and gamma p -> pi+ n. Regge phenomenology is applied at invariant collision energies above 3 GeV in order to fix the reaction amplitude. A comparision with older data on pi0- and pi+ photoproduction at theta = 180 degrees indicates that the high-energy limit as given by the Regge calculation could be reached possibly at energies of around sqrt{s} = 3 GeV. In the energy region of sqrt{s} < 2.5 GeV, covered by the new measurements of gamma p -> pi0 p differential cross sections at large angles at ELSA, JLab, and LEPS, we see no clear signal for a convergence towards the Regge results. The baryon trajectories obtained in our analysis are in good agreement with those given by the spectrum of excited baryons.
Keywords
Cite
@article{arxiv.0903.0535,
title = {Backward pion photoproduction},
author = {A. Sibirtsev and J. Haidenbauer and F. Huang and S. Krewald and U. -G. Meißner},
journal= {arXiv preprint arXiv:0903.0535},
year = {2010}
}
Comments
11 pages, 17 figures; accepted for publication by Eur. Phys. J. A