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arXiv · 1706.01379

Rare $Λ_b\to n l^+l^-$ decays in the relativistic quark-diquark picture

R. N. Faustov·V. O. Galkin
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Abstract

The form factors of the rare $Λ_b\to n l^+l^-$ decays are calculated in the framework of the relativistic quark-diquark picture of baryons with the consistent account of the relativistic effects. Their momentum transfer squared dependence is determined explicitly in the whole accessible kinematical range. The decay branching fractions, forward-backward asymmetries and the fractions of longitudinally polarized dileptons are determined. The branching fraction of the rare $Λ_b\to nμ^+μ^-$ decay are found to be ${\rm Br}(Λ_b\to nμ^+μ^-)=(3.75\pm0.38)\times10^{-8}$ and thus could be measured at the LHC. Prediction for the branching fraction of the rare radiative $Λ_b\to n γ$ decay is also given.

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R. N. Faustov, V. O. Galkin. 2017-06-05. Rare $Λ_b\to n l^+l^-$ decays in the relativistic quark-diquark picture. https://doi.org/10.1142/s0217732317501255

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