We show that a CP-violating phase can be model-independently determined from the time-independent measurement of coherent B^0_s\bar{ B}^0_s decays into (D^{ (*)\pm}_s K^{ (*)\mp})(D^{ (*)\pm}_s K^{ (*)\mp}) states at the \Upsilon (5S) resonance. This phase amounts to (-\gamma) within the standard model, where \gamma is the well-known angle of the quark mixing unitarity triangle. It is also possible to determine or constrain the B^0_s-\bar{ B}^0_s mixing parameter y_s from the same measurement.
Categories: hep-ph