$SU(3)_F$ Analysis for Beauty Baryon Decays

Speaker: Avital Dery, Cornell University

When: February 26, 2020 (Wed), 04:15PM to 05:15PM (add to my calendar)
Location: PRB 595

This event is part of the HET Seminar Series.

The measurement of rare b-baryon decays at LHCb can teach us about isospin breaking and $SU(3)F$ breaking. We perform a general $SU(3)F$ analysis of $b \to c\bar{c}s(d)$ decays of members of the beauty baryon antitriplet to a member of the light baryon octet and a singlet. Under several reasonable assumptions we find ${\cal A}(\Xi^0b \to \Lambda S)/{\cal A}(\Xi^0b \to \Xi^0 S) \approx 1/\sqrt{6} |V^{cb}V{cd}/(V^{cb}V{cs})|$ and ${\cal A}(\Lambdab \to \Sigma0 S)/{\cal A}(\Lambdab \to \Lambda S) \sim 0.02$. These two relations have been recently probed by LHCb for the case of $S = J/\Psi$. The former agrees with the measurement, while for the latter our prediction lies close to the upper bound set by LHCb. We discuss the implications of these measurements in terms of our understanding of isospin breaking as well as of dynamic mixing of the $SU(3)F$ baryon states.