Measurement of the masses and widths of the ςc (2455)+ and ςc (2520)+ baryons

Abstract

Using 980 fb-1 of data collected with the Belle detector operating at the KEKB asymmetric-energy e+e- collider, we report the measurements of the masses, and the first measurements of the instrinsic widths, of the ςc(2455)+ and ςc(2520)+ charmed baryons. We find M(ςc(2455)+)-M(Λc+)=166.17±0.05-0.07+0.16 MeV/c2, Γ(ςc(2455)+)=2.3±0.3±0.3 MeV/c2, M(ςc(2520)+)-M(Λc+)=230.9±0.5-0.1+0.5 MeV/c2, and Γ(ςc(2520)+)=17.2-2.1-0.7+2.3+3.1 MeV/c2, where the uncertainties are statistical and systematic, respectively. These measurements can be used to test models of the underlying quark structure of the ςc states.