T violation in ${\mathrm{\Lambda }}_b\to \mathrm{\Lambda }{\mathrm{\ell }}^{+}{\mathrm{\ell }}^{-}$ decays

We examine the T-odd transverse lepton and $\mathrm{\Lambda }$ polarizations in the baryonic decays of ${\mathrm{\Lambda }}_b\to \mathrm{\Lambda }{l}^{+}{l}^{-}(l=e,\mu )$ to study the T violating effects. We show that the lepton polarizations are suppressed but the $\mathrm{\Lambda }$ ones can be as large as 50% in CP violating theories beyond the standard model such as the SUSY models, which can be tested in various future hadron colliders.