Dalitz plot analysis of the decay D0 --> pi-pi+pi0 and measurement of CKM phase \gamma using B^\pm --> D_{\pi^+\pi^-\pi^0} K^\pm -- K. Mishra (Cincinnati)

lundi 1 oct. 2007, 16:30 → 17:30 Europe/Paris

Salle Grossetete (LPNHE)

The CP-violating phase \gamma of the quark-mixing Cabibbo-Kobayashi-Maskawa matrix plays a crucial role in placing constraints on the size of new physics contributions. One of the most effective method to measure this phase is to use the interference between the decays B -> D0 K and B -> D0bar K with D -> pi- pi+ pi0. We measure the magnitudes and phases of the components of the D0 --> pi-pi+pi0 decay amplitude. We apply these results to the CP violation analysis of the decay B+/- --> D(pipipi0)K+/-, where D(pipipi0) indicates a neutral D meson detected in the final state pi+pi-pi0, excluding K_S pi0. The analysis makes use of 324 million e+e- --> BB events recorded by the BaBar experiment at the PEP-II e+e- storage ring. By analyzing the pi+pi-pi0 Dalitz plot distribution and the B+/- --> D(pipipi0)K+/- branching fraction and decay rate asymmetry, we calculate parameters related to the phase gamma of the CKM unitarity triangle.