Measurement of CP violation observables and parameters for the decays B[superscript ±]→DK[superscript *±]

Abstract

We study the decay B[superscript -]→DK[superscript *-] using a sample of 379×10[superscript 6] Υ(4S)→BB̅ 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[superscript +]K[superscript -], π[superscript +]π[superscript -]), CP-odd (CP-) eigenstate (KS[superscript 0]π[superscript 0], K[subscript S][superscript 0]ϕ, K[subscript S][superscript 0]ω) or a non-CP state (K[superscript -]πsuperscript +]). We also analyze D meson decays into Ksuperscript +]πsuperscript -] from a Cabibbo-favored D̅ 0 decay or doubly suppressed D0 decay [Atwood-Dunietz-Soni (ADS) analysis]. We measure observables that are sensitive to the Cabibbo-Kobayashi-Maskawa angle γ: the partial-rate charge asymmetries A[subscript CP±], the ratios R[subscript CP±] of the B-decay branching fractions in CP± and non-CP decay, the ratio R[subscript ADS] of the charge-averaged branching fractions, and the charge asymmetry A[subscript ADS] of the ADS decays: A[subscript CP+]=0.09±0.13±0.06, A[subscript CP-]=-0.23±0.21±0.07, R[subscript CP+]=2.17±0.35±0.09, R[subscript CP-]=1.03±0.27±0.13, R[subscript ADS]=0.066±0.031±0.010, and A[subscript 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[subscript B]=0.31 with a one (two) sigma confidence level interval of [0.24, 0.38] ([0.17, 0.43]). The value r[subscript B]=0 is excluded at the 3.3 sigma level. A similar analysis excludes values of γ in the intervals [0, 7]°, [55, 111]°, and [175, 180]° ([85, 99]°) at the one (two) sigma confidence level.