Beautiful Baryons from Lattice QCD

Abstract

We perform a lattice study of heavy baryons, containing one (${\Lambda }_b$) or two $b$-quarks (${\Xi }_b$). Using the quenched approximation we obtain for the mass of ${\Lambda }_b$ $$M_{{\Lambda }_b}=5.728\pm 0.144\pm 0.018\mathrm{GeV}.$$ The mass splitting between the ${\Lambda }_b$ and the B-meson is found to increase by about 20\% if the light quark mass is varied from the chiral limit to the strange quark mass.

Comments: 11 pages, Figures obtained upon request from Borrelli@psiclu.cern.ch