Fourth generation effect on Λ < inf > b < /inf > decays

Abstract

The rare decays of the Λb baryon governed by the quark level transitions b→s are investigated in the fourth quark generation model popularly known as SM4. Recently it has been shown that SM4, which is a very simple extension of the standard model, can successfully explain several anomalies observed in the CP violation parameters of B and Bs mesons. We find that in this model due to the additional contributions coming from the heavy t′ quark in the loop, the branching ratios and other observables in rare Λb decays deviate significantly from their standard model values. Some of these modes are within the reach of the LHCb experiment and search for such channels is strongly argued. © 2010 The American Physical Society.