Doubly-charged scalar in rare decays of the Bc meson

In this paper, we study the lepton number violation processes of B-c meson induced by possible doublycharged scalars. Both the three-body decay channels and the four-body decay channels are considered. For the former, the B-c (C) over bar -> D-s(+) mu(-) mu(-) channel has the largest branching fraction 9.19 x 10(-23), and for the later channels, the B-c (C) over bar -> B-s(0) pi(+) mu(-) mu(-) channel has the largest branching ratio 1.03 x 10(-27). These results are too small to be within the current experimental precision. However, they can provide a comparison in theory with the similar cases involving an off-shell Majorana neutrino.