English

Analysis of recent CLAS data on $\Sigma ^{\ast }(1385)$ photoproduction off a neutron target

Nuclear Theory 2016-04-26 v2 High Energy Physics - Experiment High Energy Physics - Phenomenology Nuclear Experiment

Abstract

Based on recent experimental data obtained by the CLAS Collaboration, the Σ(1385)\Sigma(1385) photoproduction off a neutron target at laboratory photon energies EγE_\gamma up to 2.5\,GeV is investigated in an effective Lagrangian approach including ss-, uu-, and tt-channel Born-term contributions. The present calculation does not take into account any explicit ss-channel baryon-resonance contributions, however, in the spirit of duality, we include tt-channel exchanges of mesonic Regge trajectories. The onset of the Regge regime is controlled by smoothly interpolating between Feynman-type single-meson exchanges and full-fledged Regge-trajectory exchanges. Gauge invariance broken by the Regge treatment is fully restored by introducing contact-type interaction currents that result from the implementation of \textit{local} gauge invariance in terms of generalized Ward-Takahashi identities. The cross sections for the γnK+Σ(1385)\gamma n\to K^+\Sigma^*(1385)^- reaction are calculated and compared with experimental results from the CLAS and LEPS collaborations. Despite its simplicity, the present theoretical approach provides a good description of the main features of the data. However, the parameters fitted to the data show that the gauge-invariance-restoring contact term plays a large role which may point to large contributions from final-state interactions.

Keywords

Cite

@article{arxiv.1511.04262,
  title  = {Analysis of recent CLAS data on $\Sigma ^{\ast }(1385)$ photoproduction off a neutron target},
  author = {Xiao-Yun Wang and Jun He and Helmut Haberzettl},
  journal= {arXiv preprint arXiv:1511.04262},
  year   = {2016}
}

Comments

8 pages, 5 figures