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Measurement of the CKM parameter cos(2phi_1) using time-dependent Dalitz analysis of B0bar -> D[Ks pi+ pi-] h0

P. Krokovny
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Abstract

We present a measurement of the angle phi1 of the CKM Unitarity Triangle using time-dependent Dalitz analysis of D -> Ks pi+ pi- decays produced in neutral B meson decay to a neutral D meson and a light meson (B0bar -> D(*) h0). The method allows a direct extraction of 2phi1 and, therefore, helps to resolve the ambiguity between 2phi1 and pi-2phi1 in the measurement of sin 2phi1. We obtain sin 2phi1=0.78+-0.44+-0.22 and cos 2phi1=1.87+0.40+0.22 -0.53-0.32 The sign of cos 2phi1 is determined to be positive at 98.3% C.L.

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P. Krokovny. 2006-07-28. Measurement of the CKM parameter cos(2phi_1) using time-dependent Dalitz analysis of B0bar -> D[Ks pi+ pi-] h0. https://doi.org/10.1103/physrevlett.97.081801

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