New analysis of the radiative decay {omega}{yields}{eta}{gamma} in proton-antiproton annihilation at rest

We report on a measurement of the branching ratio of the rare decay {omega}{yields}{eta}{gamma} relative to the well known decay {omega}{yields}{pi}{sup 0}{gamma}. The {omega}'s are produced in pp(bar sign){yields}{eta}{omega} and pp(bar sign){yields}{pi}{sup 0}{omega}. Eigenstate mixing and interference effects of the {omega} and {rho}{sup 0} are taken into account, as well as coherent interference with the background. We find evidence for the non-resonant annihilation channel B(pp(bar sign){yields}{eta}{eta}{gamma})=(3.5{+-}1.3)x10{sup -5} and limit the value of B({omega}{yields}{eta}{gamma}) to the range of (0.7 to 5.5)x10{sup -4} depending on the degree of coherence with the background. (c) 2000 The American Physical Society.