Measuring B{sub s} width difference at the {Upsilon}(5s) using quantum entanglement
About 90% of B{sub s}B{sub s} pairs produced at the {Upsilon}(5s) resonance are initially B{sub s}{sup *}B{sub s}{sup *} pairs which decay radiatively to B{sub s}B{sub s}. This implies that the B{sub s}B{sub s} pair will then be in an eigenstate of charge conjugation (i.e. C=-1) and therefore in an entangled state. This allows for a determination of {Delta}{Gamma}{sub s}/{Gamma}{sub s} and the CP phase using a number of possible correlations between the decays of the two B{sub s} mesons. In particular, we consider the time integrated correlation, the time ordering asymmetry, and the time ordering-charge asymmetry, which in addition to time ordering distinguishes B{sub s} from B{sub s}, for various combinations of final states. With the statistics of about O(10{sup 7}-10{sup 8}) {Upsilon}(5s) events available at B factories, we find that the time ordering asymmetry between suitably defined hadronic and flavor specific (tagging) decays offers a promising method for determining the width difference. The corresponding time ordering-charge asymmetry can also bound the mixing phase. Similar observables involving exclusive decays are also considered. At the super B factories with O(50) times greater luminosity time ordering and time ordering-charge asymmetries between inclusive and exclusive modes may also provide additional bounds on the phases in those decays.