A search is performed for lepton-number-violating $B^-\to D^{(*)+}μ^-μ^-$ 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, ${\cal B}(B^-\to D^{+}μ^-μ^-) < 4.6 \times 10^{-8}$ and ${\cal B}(B^-\to D^{*+}μ^-μ^-) < 5.9 \times 10^{-8}$, at the 95% confidence level.
Binned efficiencies across the Dalitz plane for $B^- \to D^{+} \mu^- \mu^-$ decay. Here $\mu_1^-$ and $\mu_2^-$ represent the two muons produced in the decay, and the index specifies their ordering in transverse momentum. Efficiencies are normalized to the average over the full simulated sample.
Binned efficiencies across the Dalitz plane for $B^- \to D^{*+} \mu^- \mu^-$ decay. Here $\mu_1^-$ and $\mu_2^-$ represent the two muons produced in the decay, and the index specifies their ordering in transverse momentum. Efficiencies are normalized to the average over the full simulated sample.
Forum