Study of Bc→Dπ in the perturbative QCD approach

We investigate the branching ratios and direct CP-asymmetries of the B-c(+) -> D-0 pi(+) and B-c(+) -> D+pi(0) decays in the PQCD approach. All the diagrams with emission topology or annihilation topology are calculated strictly. A branching ratio of 10(-6) and 10(-7) for B-c(+) -> D-0 pi(+) and B-c(+) -> D+pi(0) decay is predicted, respectively. Because of the different weak phase and strong phase from penguin operator and two kinds of tree operator contributions, we predict a possible large direct CP-violation: A(CP)(dir)(B-c(+/-) -> D-0 pi(+/-)) approximate to -50% and A(CP)(dir) (B-c(+/-) -> D-+/-pi(0)) approximate to 25% when gamma = 55 degrees, which can be tested in the corning LHC.