Analysis of FCNC ${\Xi }_{QQ}\to {\Lambda }_Q{l}^{+}{l}^{-}$ decay in light-cone sum rules

Abstract

The weak decays of doubly heavy ${\Xi }_{QQ}$ baryon induced by flavor changing $b\to d$ and $c\to u$ flavor changing neutral current within the light cone sum rules are studied. Using the parallel components of the light cone distribution amplitudes for ${\Lambda }_Q$ baryon, the sum rules are constructed and analyzed for the corresponding transition form factors. Having the results for the form factors, the corresponding branching ratios for ${\Xi }_{QQ}\to {\Lambda }_Q{l}^{+}{l}^{-}$ decays are estimated. While the branching ratio due to $b\to d$ transition is around $10^{-9}$, in $c\to u$ transition case, it is found as around $10^{-13}$. Hence, ${\Xi }_{bb}\to {\Lambda }_b{l}^{+}{l}^{-}$ decay has the potential of being discovered at LHCb. However, ${\Xi }_{bb}\to {\Lambda }_b{l}^{+}{l}^{-}$ 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.

Comments: Figures for the variation of the form factors with respect to the Borel mass parameter are added. And some typos are corrected