Four-body decays of $B$ meson with lepton number violation

TL;DR

This study calculates the branching ratios of four-body B meson decays involving lepton number violation, updating limits on heavy Majorana neutrino mixing parameters and identifying promising decay channels with potentially observable rates.

Contribution

It provides new calculations of branching ratios for lepton-number violating B meson decays using updated experimental constraints on heavy Majorana neutrinos.

Findings

Branching ratio can reach about 10^{-4} for certain decay channels.

Most promising decay channels involve electrons or muons and can be observed with current experimental sensitivity.

Updated limits on heavy Majorana neutrino mixing parameters based on recent data.

Abstract

This paper is designed to calculate the branching ratio of four-body decays of $B$ meson with lepton number changed by 2. With the new experimental data limit to lepton-number violation processes, we update the upper limits of mixing parameters between heavy Majorana neutrino and charged leptons. Afterwards, we calculate the branching ratio of $B^0(P)\rightarrow D^{*-}(P_1)\ell^+_1(P_2)\ell^+_2(P_3)M_2^-(P_4)$ using the updated parameters. It is found that the most hopeful decay channel is $B^0(P)\rightarrow D^{*-}(P_1)e^+_1(P_2)e^+_2(P_3)\rho^-(P_4)$ or $B^0(P)\rightarrow D^{*-}(P_1)e(\mu)^+_1(P_2)\mu(e)^+_2(P_3)\rho^-(P_4)$, whose branching ratio can reach about $10^{-4}$ with heavy Majorana neutrino mass range around $2~\mathrm{GeV}$.