Search for lepton-number-violating $B^-\to D^{(*)+}\mu^-\mu^-$ decays

TL;DR

This paper reports a search for lepton-number-violating decays of B mesons into D mesons and muons using LHCb data, setting upper limits on their branching fractions due to no observed signal.

Contribution

First search for these specific lepton-number-violating B decays using 13 TeV LHCb data, establishing new upper limits on their branching fractions.

Findings

No significant signal observed.

Upper limits set on branching fractions: <4.6×10^{-8} and <5.9×10^{-8}.

Results constrain theories predicting lepton-number violation.

Abstract

A search is performed for lepton-number-violating $B^-\to D^{(*)+}\mu^-\mu^-$ decays, using data collected by the LHCb experiment in proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.4 fb$^{-1}$. No significant signal is observed, and upper limits are set on the branching fractions, ${\cal B}(B^-\to D^{+}\mu^-\mu^-) < 4.6 \times 10^{-8}$ and ${\cal B}(B^-\to D^{*+}\mu^-\mu^-) < 5.9 \times 10^{-8}$, at the 95% confidence level.