T-Violating Triple-Product Correlations in Charmless Lambda_b Decays
  Using factorization, we compute, within the standard model, the T-violating triple-product correlations in the charmless decays Lambda_b -> F_1 F_2, where F_1 is a light spin-1/2 baryon and F_2 is a pseudoscalar (P) or vector (V) meson. We find a large triple-product asymmetry of 18% for the decay Lambda_b -> p K^-. However, for other classes of Lambda_b -> F_1 P decays, the asymmetry is found to be at most at the percent level. For Lambda_b -> F_1 V decays, we find that all triple-product asymmetries are small (at most O(1%)) for a transversely-polarized V, and are even smaller for longitudinal polarization. Our estimates of the nonfactorizable contributions to these decays show them to be negligible, and we describe ways of testing this. 
Wafia Bensalem, Alakabha Datta and David London