Asymmetry in the decay $Ω^-\toΞ^-γ$

Abstract

We consider the asymmetry in the decay $Ω^-\rightarrowΞ^-γ$ assuming that a Vector Meson Dominance approach for the $s\rightarrow dγ$ transition gives the dominant contribution. Since in this long-distance approximation the decay is due to a single quark transition $s\rightarrow dγ$, the angular distribution asymmetry is given by the single positive asymmetry parameter $α_h = \frac{M^2_s-M^2_d}{M^2_s+M^2_d} = 0.4\pm0.1$. We also discuss the asymmetry in $Ξ\rightarrow Σ^-γ$, which is expected to be between -0.2 and 0.3.