Baryons with two heavy quarks: Masses, production, decays, and detection

The large number of Bc mesons observed by LHCb suggests a sizable cross section for producing doubly heavy baryons in the same experiment. Motivated by this, we estimate masses of the doubly heavy $J=1/2$ baryons Ξcc, Ξbb, and Ξbc, and their $J=3/2$ hyperfine partners, using a method which accurately predicts the masses of ground-state baryons with a single heavy quark. We obtain M(Ξcc)=3627±12 MeV, M(Ξcc*)=3690±12 MeV, M(Ξbb)=10162±12 MeV, M(Ξbb*)=10184±12 MeV, M(Ξbc)=6914±0ex0ex13 MeV, M(Ξ^'bc)=6933±12 MeV, and M(Ξbc*)=6969±14 MeV. As a byproduct, we estimate the hyperfine splitting between Bc* and Bc mesons to be 68±8 MeV. We discuss P-wave excitations, production mechanisms, decay modes, lifetimes, and prospects for detection of the doubly heavy baryons.