A Hidden Local Symmetry Approach to Rho Meson Photoproduction

TL;DR

This paper develops a hidden local symmetry model for rho meson photoproduction, emphasizing the importance of sigma exchange for neutral rho and magnetic moments for charged rho, aligning theoretical predictions with experimental data.

Contribution

It introduces a novel hidden local symmetry framework for rho meson photoproduction, incorporating sigma exchange and magnetic moments to improve agreement with experiments.

Findings

Sigma exchange is essential for neutral rho photoproduction.

Charged rho meson magnetic moments significantly affect cross sections.

T-channel processes dominate, useful for studying unstable particle structures.

Abstract

We study photoproduction of rho mesons in a model of hidden local symmetry. The rho meson is introduced as a hidden gauge boson and a phenomenological rho meson-nucleon Lagrangian is constructed respecting chiral symmetry. It is shown that the sigma exchange interaction is needed for neutral rho meson photoproduction to reproduce the experimental cross sections. For charged rho meson photoproduction, the model takes into account the rho meson magnetic moments from the three-point vertex in the kinetic terms. We show that the magnetic moment of the charged rho meson has a significant effect on the total cross sections through the rho meson exchange process, which is proportional to the energy of the photon. The t-channel dominance may be used for the study of structures of various unstable particles.