We study the decay B--> DK*- using a sample of 379x10(6) Upsilon(4S)-> BB events collected with the BABAR detector at the PEP-II B factory. We perform a Gronau-London-Wyler analysis where the D meson decays into either a CP-even (CP+) eigenstate (K+K-, pi(+)pi(-)), CP-odd (CP-) eigenstate (K-S(0)pi(0), K-S(0)phi, K-S(0)omega) or a non-CP state (K-pi(+)). We also analyze D meson decays into K+pi(-) from a Cabibbo-favored D-0 decay or doubly suppressed D-0 decay [Atwood-Dunietz-Soni (ADS) analysis]. We measure observables that are sensitive to the Cabibbo-Kobayashi-Maskawa angle gamma: the partial-rate charge asymmetries A(CP +/-), the ratios R-CP +/- of the B-decay branching fractions in CP +/- and non-CP decay, the ratio R-ADS of the charge-averaged branching fractions, and the charge asymmetry A(ADS) of the ADS decays: A(CP+)=0.09 +/- 0.13 +/- 0.06, A(CP-)=-0.23 +/- 0.21 +/- 0.07, RCP+=2.17 +/- 0.35 +/- 0.09, RCP-=1.03 +/- 0.27 +/- 0.13, R-ADS=0.066 +/- 0.031 +/- 0.010, and A(ADS)=-0.34 +/- 0.43 +/- 0.16, where the first uncertainty is statistical and the second is systematic. Combining all the measurements and using a frequentist approach yields the magnitude of the ratio between the Cabibbo-suppressed and favored amplitudes, r(B)=0.31 with a one (two) sigma confidence level interval of [0.24, 0.38] ([0.17, 0.43]). The value r(B)=0 is excluded at the 3.3 sigma level. A similar analysis excludes values of gamma in the intervals [0, 7]degrees, [55, 111]degrees, and [175, 180]degrees ([85, 99]degrees) at the one (two) sigma confidence level.

Measurement of CP violation observables and parameters for the decays B-+/--> DK*+/-

Gaz A;Cecchi A;Perez A;Angelini C;Batignani G;Baracchini E;Ferroni F;Li S;Pan B;
2009

Abstract

We study the decay B--> DK*- using a sample of 379x10(6) Upsilon(4S)-> BB events collected with the BABAR detector at the PEP-II B factory. We perform a Gronau-London-Wyler analysis where the D meson decays into either a CP-even (CP+) eigenstate (K+K-, pi(+)pi(-)), CP-odd (CP-) eigenstate (K-S(0)pi(0), K-S(0)phi, K-S(0)omega) or a non-CP state (K-pi(+)). We also analyze D meson decays into K+pi(-) from a Cabibbo-favored D-0 decay or doubly suppressed D-0 decay [Atwood-Dunietz-Soni (ADS) analysis]. We measure observables that are sensitive to the Cabibbo-Kobayashi-Maskawa angle gamma: the partial-rate charge asymmetries A(CP +/-), the ratios R-CP +/- of the B-decay branching fractions in CP +/- and non-CP decay, the ratio R-ADS of the charge-averaged branching fractions, and the charge asymmetry A(ADS) of the ADS decays: A(CP+)=0.09 +/- 0.13 +/- 0.06, A(CP-)=-0.23 +/- 0.21 +/- 0.07, RCP+=2.17 +/- 0.35 +/- 0.09, RCP-=1.03 +/- 0.27 +/- 0.13, R-ADS=0.066 +/- 0.031 +/- 0.010, and A(ADS)=-0.34 +/- 0.43 +/- 0.16, where the first uncertainty is statistical and the second is systematic. Combining all the measurements and using a frequentist approach yields the magnitude of the ratio between the Cabibbo-suppressed and favored amplitudes, r(B)=0.31 with a one (two) sigma confidence level interval of [0.24, 0.38] ([0.17, 0.43]). The value r(B)=0 is excluded at the 3.3 sigma level. A similar analysis excludes values of gamma in the intervals [0, 7]degrees, [55, 111]degrees, and [175, 180]degrees ([85, 99]degrees) at the one (two) sigma confidence level.
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Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/20.500.12571/2731
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