The annihilation decays $B_c^{-}\to {\eta }^{{}^{\prime }}(\eta ,{\pi }^0)l^{-}\bar{\nu }$

Abstract

We investigate the simileptonic OZI-forbidden annihilation decays $B_c^{-}\to {\eta }^{{}^{\prime }}(\eta ,{\pi }^0)l^{-}\bar{\nu }$ for $l=\mu ,e$ in the perturbative QCD, and carry out a precise calculation without any approximation for the one-loop contributions, which involves integrals of 4- and 5-point loop functions. Our results show that the branching ratios of decays $B_c^{-}\to {\eta }^{{}^{\prime }}{l}^{-}\bar{\nu }$, $B_c^{-}\to \eta l^{-}\bar{\nu }$ and $B_c^{-}\to {\pi }^0{l}^{-}\bar{\nu }$, turn out to be of orders $10^{-4}$, $10^{-5}$ and $10^{-6}$, respectively, which could be observable in the future experiments at the LHC.

Comments: 15 pages, 1 figures. To be appeared in Phys.Rev.D