Eur. Phys. J. A (2014) 50: 126
https://doi.org/10.1140/epja/i2014-14126-6

Regular Article - Theoretical Physics

Mass spectra and Regge trajectories of light mesons in the Bethe-Salpeter approach

Institut für Theoretische Physik, Justus-Liebig-Universität Giessen, 35392, Giessen, Germany

^* e-mail: christian.fischer@theo.physik.uni-giessen.de

Received: 23 June 2014
Revised: 9 July 2014
Accepted: 13 July 2014
Published online: 13 August 2014

Abstract

We extend the calculation of relativistic bound states of a fermion anti-fermion pair in the Bethe-Salpeter formalism to the case of total angular momentum . Together with results for this allows for the investigation of Regge trajectories in this approach. We exemplify such a study for ground and excited states of light unflavored mesons as well as strange mesons within the rainbow-ladder approximation. For the - and -meson we find a linear Regge trajectory within numerical accuracy. Discrepancies with experiment in other channels highlight the need to go beyond rainbow ladder and to consider effects such as state mixing and more sophisticated quark-antiquark interaction kernels.