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Improved measurement of CP-violating parameters in rho+rho- decays

A. Somov·A. J. Schwartz
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Abstract

We present a measurement of the CP-violating asymmetry in rho+rho- decays using 535 million BBbar pairs collected with the Belle detector at the KEKB e+e- collider. We measure CP-violating coefficients A = 0.16 +- 0.21(stat) +- 0.07 (syst) and S = 0.19 +- 0.30(stat) +- 0.07 (syst}. These values are used to determine the unitarity triangle angle phi_2 using an isospin analysis; the solution consistent with Standard Model lies in the range 53 < phi_2 < 114 deg. at 90 C.L.

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A. Somov, A. J. Schwartz. 2007-05-01. Improved measurement of CP-violating parameters in rho+rho- decays. https://doi.org/10.1103/physrevd.76.011104

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