CP violation in the Bs0 system

Experimental and theoretical studies of CP violation in the B-s(0) system are reviewed. Updated predictions for the mixing parameters of the B-s(0) mesons expected in the standard model (SM) are given, namely, the mass difference Delta M-s(SM) = 18.3 +/- 2.7 ps(-1), the decay rate difference Delta Gamma(SM)(s) = 0.085 +/- 0.015 ps(-1), and the flavor-specific CP asymmetry a(fs)(s,SM) = (2.22 +/- 0.27) x 10(-5) and the equivalent quantities in the B-0 sector. Current experimental values of Delta M-s and Delta Gamma(s) agree with remarkable precision with theoretical expectations. This agreement supports the applicability of theoretical tools such as the heavy quark expansion to these decays. CP-violating studies in the B-s(0) system provide essential information to test the SM expectations and to unveil a possible contribution of the new physics (NP). NP effects on Delta M-s of the order of 15% are still possible. The CP phase phi(s) due to CP violation in interference of decays and mixing can accommodate effects of the order of O(100%). The semileptonic CP asymmetry a(sl)(s) due to CP violation in mixing could still be a factor of 130 larger than its robust SM expectation and thus provides a very clean observable for NP searches. Theoretical improvements that are necessary to make full use of the experimental precision are discussed.