Theoretical Study of the \gamma\gamma-->meson-meson Reaction
Abstract
We present a unified picture which studies simultaneously the gamma gamma-->pi^+ pi^-, pi^0 pi^0, K^+ K^-, K^0 bar{K}^0, pi^0 eta reactions up to about sqrt(s)=1.4 GeV reproducing the experimental cross sections. The present work implements in an accurate way the final state interactions of the meson-meson system, which is shown to be essential in order to reproduce the data, particularly the L=0 channel. This latter channel is treated here following a recent theoretical work in which the meson-meson amplitudes are well reproduced and the f_0, a_0, sigma resonances show up clearly as poles of the t matrix. The present work, as done in earlier ones, also incorporates elements of chiral symmetry and exchange of vector and axial resonances in the crossed channels, as well as a direct coupling to the f_2(1270) and a_2(1320) resonances. We also evaluate the decay width of the f_0(980) and a_0(980) resonances into the gamma-gamma channel.
Keywords
Cite
@article{arxiv.hep-ph/9706487,
title = {Theoretical Study of the \gamma\gamma-->meson-meson Reaction},
author = {J. A. Oller and E. Oset},
journal= {arXiv preprint arXiv:hep-ph/9706487},
year = {2010}
}
Comments
20 pages, 13 figures, LaTeX. Only significant change in the calculation of \gamma\gamma-->pi^+ pi^- from the more careful treatment of the tail of the f_2(1270) resonance