Bs0–B¯s0 oscillations as a new tool to explore CP violation in Ds± decays

Abstract CP violation in B s 0 – B ¯ s 0 oscillations is expected at the 10 − 5 level in the Standard Model but could be enhanced by New Physics. Using B s 0 → D s − l + ν l decays, LHCb has recently reported the new result ( 0.39 ± 0.33 ) × 10 − 2 of the corresponding observable a sl s . We point out that other current B decay data imply a sl s = ( 0.004 ± 0.075 ) × 10 − 2 . In view of this strong constraint, we propose to use B s 0 → D s − l + ν l and similar flavor-specific decays as a new tool to determine both the production asymmetry between B s 0 and B ¯ s 0 mesons, and the CP asymmetry in the subsequent D s ± decays. The former serves as input for analyses of CP violation in B s 0 channels, with significant room for improvement, while the latter offers an exciting laboratory for New Physics.