Comments on "Interference phenomena in the $J^{p} = 1/2^-$ - wave in $\eta$ photoproduction" by A.V. Anisovich et al. [arXiv:1501.02093]

TL;DR

This paper critiques a previous study claiming a narrow structure in eta photoproduction is due to interference effects, suggesting possible numerical errors and questioning the original interpretation.

Contribution

It provides a critical analysis of prior claims about interference effects causing narrow structures in eta photoproduction, highlighting potential numerical errors.

Findings

Questioned the interpretation of narrow structures as interference effects.

Identified possible numerical errors in the original analysis.

Challenged the conclusions drawn about the $J^{p} = 1/2^-$ wave.

Abstract

The authors of arXiv:1501.02093v1 claimed that " ... narrow structure observed in the excitation function of $\gamma n \to \eta n$ can be reproduced fully with a particular interference pattern in the $J^{p} = 1/2^-$ partial wave..." while a narrow structure in Compton scattering off the neutron is "...a stand-alone observation unrelated to the structure observed in $\gamma n \to \eta n$...". The source for the second statement may be a simple numerical error. If so, the interpretation of the narrow structure in $\gamma n \to \eta n$ as interference effects in the $J^{p} = 1/2^-$-wave and some conclusions from arXiv:1501.02093v1 are questionable.