Investigating in-medium properties of the $\omega$ meson via the   $\omega\rightarrow\pi^0\gamma$ decay
  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. 
Janus Weil, Ulrich Mosel, Volker Metag
nucl-th hep-ph nucl-ex