Using 586pb -1 of e +e - collision data acquired at √s=4.170GeV with the CLEO-c detector at the Cornell Electron Storage Ring, we report the first observation of Ds*+→Ds+e +e - with a significance of 5.3σ. The ratio of branching fractions B(Ds*+→Ds+e +e -)/ B(Ds*+→Ds+γ) is measured to be [0.72-0.13+0.15(stat)±0. 10(syst)]%, which is consistent with theoretical expectations.
|Original language||English (US)|
|Journal||Physical Review D - Particles, Fields, Gravitation and Cosmology|
|State||Published - Oct 10 2012|