Selected vector-meson decay-distributions in reactions of polarized   photons with protons
  We develop a formalism for studying vector meson ($V$) photo-production at the proton ($p$) with polarized photons, $\vec\gamma p \to V p $, through an analysis of the decay distribution in the channel $V\to\pi^0\gamma$. We show that this decay distribution differs noticeably from the distributions of purely hadronic decays, like $\phi\to K^+K^-$, $\omega\to \pi^0\pi^+\pi^-$. Formulas for the decay distributions are presented which are suitable for data analysis and interpretation. 
A.I. Titov and B. Kampfer