Exclusive semileptonic decays of $\Lambda_b \to \Lambda l^{+} l^{-}$ in supersymmetric theories

Understand

The weak decays of $\Lambda_b \to \Lambda l^{+} l^{-}$ ($l=e, \mu$) are investigated in Minimal Supersymmetric Standard Model (MSSM) and also in Supersymmetric (SUSY) SO(10) Grand Unified Models.

• In MSSM the special attention is paid to the Neutral Higgs Bosons (NHBs) as they make quite a large contribution in exclusive $B \to X_{s} l^{+} l^{-}$ decays at large $\tan{\beta}$ regions of parameter space of SUSY models, since part of SUSY contributions is proportional to $\tan^{3}{\beta}$.
• The analysis of decay rate, forward-backward asymmetries, lepton polarization asymmetries and the polarization asymmetries of $\Lambda $ baryon in $\Lambda_b \to \Lambda l^{+} l^{-}$ show that the values of these physical observables are greatly modified by the effects of NHBs.
• In SUSY SO(10) GUT model, the new physics contribution comes from the operators which are induced by the NHBs penguins and also from the operators having chirality opposite to that of the corresponding SM operators.