Investigating in-medium properties of the $\omega$ meson via the $\omega\rightarrow\pi^0\gamma$ decay

TL;DR

This study assesses methods to probe the in-medium properties of the $$ meson in photoproduction experiments, highlighting the challenges and potential of various observables using the GiBUU transport model.

Contribution

It demonstrates that invariant mass spectra are affected by final-state interactions, while transparency ratio, excitation function, and momentum spectrum are more reliable for studying in-medium properties.

Findings

Invariant mass spectrum is heavily influenced by pion final-state interactions.

Transparency ratio, excitation function, and momentum spectrum are less affected by final-state interactions.

These observables can effectively access the in-medium properties of the $$ meson.

Abstract

We investigate the feasibility of studying in-medium properties of the $\omega$ meson in photoproduction experiments via the decay $\omega\rightarrow\pi^0\gamma$. We use the GiBUU transport model to compare different methods of obtaining in-medium information, such as the invariant mass spectrum, transparency ratio, excitation function and momentum spectrum. We show that the final-state interaction of the pion poses a major obstacle for the interpretation of the invariant mass spectrum. The other three observables turn out to be fairly independent of final-state interactions and thus can give access to the $\omega$'s in-medium properties.