Mass splittings within heavy baryon isospin multiplets in chiral perturbation theory

Abstract

We calculate the mass splittings within the heavy baryon isospin multiplets Sigma(c(b)) and Xi(')(c(b)) in chiral perturbation theory to leading one-loop order. The pattern of the mass splittings in the Sigma(c) iso-triplet, which is different from that of any other known isospin multiplet, can be explained. We predict m(Xi c'+) - m(Xi c'0) = -0.2 +/- 0.6 MeV, m Xi(b'0) - m Xi(b'0) = -4.0 +/- 1.9 MeV and the mass of the Sigma(b0) to be 5810.3 +/- 1.9 MeV