Triply Heavy Baryons and Heavy Quark Spin Symmetry

Abstract

We study the semileptonic $b\to c$ decays of the lowest-lying triply-heavy baryons made from $b$ and $c$ quarks in the limit $m_b,m_c\gg {\Lambda }_{\mathrm{QCD}}$ and close to the zero recoil point. The separate heavy quark spin symmetries strongly constrain the matrix elements, leading to single form factors for $ccb\to ccc$, $bbc\to ccb$, and $bbb\to bbc$ baryon decays. We also study the effects on these systems of using a $Y$-shaped confinement potential, as suggested by lattice QCD results for the interaction between three static quarks.

Comments: 12 latex pages, 3 figures, 3 tables. Enlarged discussion. New references added