Using imprecise tags of CP eigenstates in Bs and the determination of the CKM phase γ

We consider the possibility of studying the CP properties of various Bs decays at an electron–positron machine tuned to the ϒ(5S). Since decay modes of the Bs with definite CP are relatively rare, we suggest that the use of more common modes which are not pure CP eigenstates may allow the determination of the CKM phase γ. By studying the degree of correlation between different decay modes at a ϒ(5S) it is possible to determine the degree of affinity of each decay mode to a CP eigenstate. Once this is known, the correlation between a decay mode with a greater affinity to a particular CP eigenstate with a mode such as Ds+K− gives a determination of the phase γ.