Time-reversal asymmetries in Λb semileptonic decays

We study the decays of Ab -> Aco -> Bnf thorn l-nu over bar with l 1/4 e, mu,tau, where Bn and f are the daughter baryon and the rest of the particles in Ac cascade decays, respectively. In particular, we examine the full angular distributions with polarized Ab and lepton mass effects, in which the time-reversal asymmetries are identified. We concentrate on the decay modes of Ab -> Aco -> pK-pi thorn thorn l-nu over bar to demonstrate their experimental feasibility. We show that the observables associated with the time-reversal asymmetries are useful to search for new physics as they vanish in the standard model. We find that they are sensitive to the right-handed current from new physics, and possible to be observed at LHCb.

Automated summary

This study investigates a decay mode and examines the observable quantities associated with time-reversal asymmetries for the purpose of searching for new physics.