CP asymmetries in scalar bottom quark decays

Abstract

We propose CP asymmetries based on triple product correlations in the decays sbottom_m -> top chargino_j with subsequent decays of top and chargino_j. For the subsequent chargino_j decay into a leptonic final state l^- νneutralino_1 we consider the three possible decay chains chargino_j -> l^- sneutrino -> l^- νneutralino_1, chargino_j -> slepton_n ν-> l^- νneutralino_1 and chargino_j -> W^- neutralino_1 -> l^- νneutralino_1. We consider two classes of CP asymmetries. In the first class it must be possible to distinguish between different leptonic chargino_j decay chains, whereas in the second class this is not necessary. We consider also the 2-body decay chargino_j -> W^- neutralino_1, and we assume that the momentum of the W boson can be measured. Our framework is the minimal supersymmetric standard model with complex parameters. The proposed CP asymmetries are non-vanishing due to non-zero phases for the parameters μand/or A_b. We present numerical results and estimate the observability of these CP asymmetries.