The weak decays of doubly heavy ${\mathrm{\Xi }}_{QQ}$ baryon induced by flavor changing $b\to d$ and $c\to u$ flavor changing neutral current within the light-cone sum rules are studied. The sum rules are constructed and analyzed for the corresponding transition form factors using the parallel components of the light-cone distribution amplitudes for ${\mathrm{\Lambda }}_Q$ baryon. Having the results for the form factors, the corresponding branching ratios for ${\mathrm{\Xi }}_{QQ}\to {\mathrm{\Lambda }}_Q{l}^{+}{l}^{-}$ 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, ${\mathrm{\Xi }}_{bb}\to {\mathrm{\Lambda }}_b{l}^{+}{l}^{-}$ decay has the potential of being discovered at LHCb. However, ${\mathrm{\Xi }}_{bb}\to {\mathrm{\Lambda }}_b{l}^{+}{l}^{-}$ 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.

中文翻译：

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光锥和规则中FCNCΞQQ→ΛQl+l−衰减分析

双重的弱衰变${\mathrm{\Xi }}_{问问}$风味变化诱发的重子$b\to d$和$C\to 你$研究了光锥和规则内的风味变化中性电流。使用光锥分布幅度的平行分量构建和分析相应的过渡形状因子的求和规则${\mathrm{\Lambda }}_{问}$重子。有了形状因子的结果，相应的分支比${\mathrm{\Xi }}_{问问}\to {\mathrm{\Lambda }}_{问}{l}^{+}{l}^{-}$估计衰减。而支化率由于$b\to d$过渡就在身边${10}^{-9}$， 在$C\to 你$过渡情况，它被发现在${10}^{-13}$. 因此，${\mathrm{\Xi }}_{bb}\to {\mathrm{\Lambda }}_b{l}^{+}{l}^{-}$衰变有可能在 LHCb 上被发现。然而，${\mathrm{\Xi }}_{bb}\to {\mathrm{\Lambda }}_b{l}^{+}{l}^{-}$由于获得的支化率值极小，因此难以测量。我们的分支率结果也与光前方法的结果进行了比较。