Observation of the isospin-violating decay Ds(*+) -> Ds(+) pi(0)

Abstract

Using data collected with the CLEO II detector, we have observed the isospin-violating decay D-s(*+) --> D-s(+) pi(0). The decay rate for this mode, relative to the dominant radiative decay, is found to be Gamma(D-s(*+) --> D-s(+) pi(0))/Gamma(D-s(*+) --> D(s)(+)gamma) = 0.062(-0.018)(+0.020) +/- 0.022.