Analysis of FCNC ΞQQ→ΛQl+l− decay in light-cone sum rules

Abstract

The weak decays of doubly heavy ${\mathrm{\ensuremath{\Xi}}}_{QQ}$ baryon induced by flavor changing $b\ensuremath{\rightarrow}d$ and $c\ensuremath{\rightarrow}u$ flavor changing neutral current within the light-cone sum rules are studied. The sum rules are constructed and analyzed for the corresponding transition form factors using the parallel components of the light-cone distribution amplitudes for ${\mathrm{\ensuremath{\Lambda}}}_{Q}$ baryon. Having the results for the form factors, the corresponding branching ratios for ${\mathrm{\ensuremath{\Xi}}}_{QQ}\ensuremath{\rightarrow}{\mathrm{\ensuremath{\Lambda}}}_{Q}{l}^{+}{l}^{\ensuremath{-}}$ decays are estimated. While the branching ratio due to $b\ensuremath{\rightarrow}d$ transition is around ${10}^{\ensuremath{-}9}$, in $c\ensuremath{\rightarrow}u$ transition case, it is found as around ${10}^{\ensuremath{-}13}$. Hence, ${\mathrm{\ensuremath{\Xi}}}_{bb}\ensuremath{\rightarrow}{\mathrm{\ensuremath{\Lambda}}}_{b}{l}^{+}{l}^{\ensuremath{-}}$ decay has the potential of being discovered at LHCb. However, ${\mathrm{\ensuremath{\Xi}}}_{bb}\ensuremath{\rightarrow}{\mathrm{\ensuremath{\Lambda}}}_{b}{l}^{+}{l}^{\ensuremath{-}}$ is difficult to be measured due to the extremely small values of obtained branching ratio. Our results on the branching ratio are also compared with the results of the light-front approach.