Speaker
Description
The existence of hybrid mesons, in which an excited gluonic field contributes to the meson properties, is strongly supported by both theory and experiment. The best experimental candidate for the lightest hybrid meson is the spin-exotic π1(1600), observed in pion production at the COMPASS experiment via its decay into ηπ and η'π. Searching for this state in photoproduction is one of the main goals of the GlueX experiment at Jefferson Lab. Understanding the dynamics and backgrounds is essential for isolating the π1(1600) signal. In the production of ηπ and η'π at high energies, the double-Regge mechanism effectively describes the COMPASS data above the resonance region, including the observed forward-backward asymmetry. In this talk, I present a double-Regge model for ηπ and η'π photoproduction recently developed by JPAC. The model is based on a double-vector exchange with coupling parameters fixed entirely by experimental data, and the reggeization is performed with proper attention to the analytic structure of the amplitude. I will show predictions for cross sections and asymmetries, which will be tested against upcoming GlueX data.
