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Model Independent Bound on the Unitarity Triangle from CP Violation in B-> pi+ pi- and B-> psi K_S

Gerhard Buchalla·A. Salim Safir
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Abstract

We derive model independent lower bounds on the CKM parameters (1-rhobar) and etabar as functions of the mixing-induced CP asymmetry S in B-> pi+ pi- and sin(2 beta) from B->psi K_S. The bounds do not depend on specific results of theoretical calculations for the penguin contribution to B-> pi+ pi-. They require only the very conservative condition that a hadronic phase, which vanishes in the heavy-quark limit, does not exceed 90 degrees in magnitude. The bounds are effective if -sin(2 beta) < S < 1. Dynamical calculations indicate that the limits on rhobar and etabar are close to their actual values.

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Gerhard Buchalla, A. Salim Safir. 2003-10-17. Model Independent Bound on the Unitarity Triangle from CP Violation in B-> pi+ pi- and B-> psi K_S. https://doi.org/10.1103/physrevlett.93.021801

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