Searches for the baryon- and lepton-number violating decays $B^0\rightarrow\Lambda_c^+\ell^-$, $B^-\rightarrow\Lambda\ell^-$, and $B^-\rightarrow\bar{\Lambda}\ell^-$

TL;DR

This paper searches for baryon- and lepton-number violating B meson decays involving Lambda baryons and leptons, setting upper limits on their branching fractions due to no significant signals observed.

Contribution

It provides the first experimental upper limits on these rare decays, probing physics beyond the standard model.

Findings

No significant signals observed in any decay mode.

Upper limits on branching fractions range from 3.2 to 520 times 10^{-8}.

Constraints improve understanding of baryon- and lepton-number violation.

Abstract

Searches for $B$ mesons decaying to final states containing a baryon and a lepton are performed, where the baryon is either $\Lambda_c$ or $\Lambda$ and the lepton is a muon or an electron. These decays violate both baryon and lepton number and would be a signature of physics beyond the standard model. No significant signal is observed in any of the decay modes, and upper limits in the range $(3.2-520) \times 10^{-8}$ are set on the branching fractions at the 90% confidence level.