Observation of an excited charm baryon Ωc* decaying to Ωc0γ

We report the first observation of an excited singly charmed baryon Omega(*)(c) (css) in the radiative decay Omega(0)(c)gamma, where the Omega(0)(c) baryon is reconstructed in the decays to the final states Omega(-)pi(+), Omega(-)pi(+)pi(0), Omega(-)pi(+)pi(-)pi(+), and Xi K--(-)pi(+)pi(+). This analysis is performed using a data set of 230.7 fb(-1) collected by the BABAR detector at the PEP-II asymmetric-energy B factory at the Stanford Linear Accelerator Center. The mass difference between the Omega(*)(c) and the Omega(0)(c) baryons is measured to be 70.8 +/- 1.0(stat) +/- 1.1(syst) MeV/c(2). We also measure the ratio of inclusive production cross sections of Omega(*)(c) and Omega(0)(c) in e(+)e(-) annihilation.