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Lifetime Differences, direct CP Violation and Partial Widths in D0 Meson Decays to K+K- and pi+pi-

S. E. Csorna·CLEO Collaboration
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Abstract

We describe several measurements using the decays D0->K+K- and pi+pi-. We find the ratio of partial widths, Gamma(D0->K+K-)/Gamma(D0->pi+pi-), to be 2.96+/-0.16+/-0.15, where the first error is statistical and the second is systematic. We observe no evidence for direct CP violation, obtaining A_CP(KK) = (0.0+/-2.2+/-0.8)% and A_CP(pipi = (1.9+/-3.2+/-0.8)%. In the limit of no CP violation we measure the mixing parameter y_CP = -0.012+/-0.025+/-0.014 by measuring the lifetime difference between D0->K+ K- or pi+pi- and the CP neutral state, D0->K-pi+. We see no evidence for mixing.

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S. E. Csorna, CLEO Collaboration. 2001-11-07. Lifetime Differences, direct CP Violation and Partial Widths in D0 Meson Decays to K+K- and pi+pi-. https://doi.org/10.1103/physrevd.65.092001

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