We report the first observation of two narrow charmed strange baryons decaying to Ξ+ cγ and Ξ0 Cγ, respectively, using data from the CLEO II detector at the Cornell Electron Storage Ring. We interpret the observed signals as the Ξ+′ c(c(u)) and Ξ0′ cγ(c(sd)), the symmetric partners of the well-established antisymmetric Ξ+ c(c[su]) and Ξ0 c(c[sd]). The mass differences M(Ξ+′ c)-M(Ξ+ c) and M(Ξ0′ c)-M(Ξ0 c) have been measured to be 107.8±1.7±2.5 and 107.0±1.4±2.5MeV/c2, respectively.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)