Regge behaviors in orbitally excited spectroscopy of charmed and bottom baryons

Abstract

Stimulated by recent progress made by the LHCb Collaboration in discoveries of new bottom baryons, e.g., the ${\Xi }_b(6227{)}^{-}$ and the ${\Sigma }_b(6097{)}^{\pm }$, we re-examine the orbitally excited spectrum of the charmed and bottom baryons using Regge approach in the heavy quark-diquark picture. The results indicate that the spin-averaged mass spectrum of the orbitally-excited charmed and bottom baryons can be described by a linear Regge relation, which is derived from the rotating QCD string model. By giving further mass-splitting analysis of spin-dependent interactions, we explain the baryons ${\Xi }_b(6227{)}^{-}$ and the ${\Sigma }_b(6097{)}^{\pm }$,and the ${\Sigma }_c(2800)$ and ${\Xi }_c^{\prime }(2930)$ to be the $1P$%-wave baryons, all with the spin-parity $J^P=3/2^{-}$ preferably. Mass prediction of the bottom baryon ${\Xi }_b$ in its P- and D-waves are presented, providing clues for the coming experiments like the LHCb to find them.

Comments: The Latex file with 11 pages is updated in a form with 15 pages, with more systematic calculations and supporting evidences from experimental data added. A discussions and a more appendix C added and appendixes A and C updated