ηproduction off the proton in a Regge-plus-chiral quark approach

Abstract

A chiral constituent quark model approach, embodying $s$- and $u$-channel exchanges, complemented with a Reggeized treatment for the $t$ channel is presented. A model is obtained allowing data for ${\ensuremath{\pi}}^{\ensuremath{-}}p\ensuremath{\rightarrow}\ensuremath{\eta}n$ and $\ensuremath{\gamma}p\ensuremath{\rightarrow}\ensuremath{\eta}p$ to be described satisfactorily. For the latter reaction, recently released data by the CLAS and CBELSA/TAPS Collaborations in the system total energy range $1.6\ensuremath{\lesssim}W\ensuremath{\lesssim}2.8$ GeV are well reproduced by the inclusion of Reggeized trajectories instead of simple $\ensuremath{\rho}$ and $\ensuremath{\omega}$ poles. The contribution from ``missing'' resonances, with masses below 2 GeV, is found to be negligible in the considered processes.