Abstract
A binned Dalitz plot analysis of B ± → DK ± decays, with \( D\to {K}_{{}^{\mathrm{S}}}^0{\pi}^{+}{\pi}^{-} \) and \( D\to {K}_{{}^{\mathrm{S}}}^0{K}^{+}{K}^{-} \), is performed to measure the CP-violating observables x ± and y ±, which are sensitive to the Cabibbo-Kobayashi-Maskawa angle γ. The analysis exploits a sample of proton-proton collision data corresponding to 3.0 fb−1 collected by the LHCb experiment. Measurements from CLEO-c of the variation of the strong-interaction phase of the D decay over the Dalitz plot are used as inputs. The values of the parameters are found to be x + = (−7.7 ± 2.4 ± 1.0 ± 0.4) × 10− 2, x − = (2.5 ± 2.5 ± 1.0 ± 0.5) × 10− 2, y + = (−2.2 ± 2.5 ± 0.4 ± 1.0) × 10− 2 and y − = (7.5 ± 2.9 ± 0.5 ± 1.4) × 10− 2. The first, second, and third uncertainties are the statistical, the experimental systematic, and that associated with the precision of the strong-phase parameters. These are the most precise measurements of these observables and correspond to γ = (62 + 15− 14 )°, with a second solution at γ → γ + 180°, and r B = 0.080 + 0.019− 0.021 , where r B is the ratio between the suppressed and favoured B decay amplitudes.
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The LHCb collaboration., Aaij, R., Adeva, B. et al. Measurement of the CKM angle γ using B ± → DK ± with D → K 0 S π + π −, K 0 S K + K − decays. J. High Energ. Phys. 2014, 97 (2014). https://doi.org/10.1007/JHEP10(2014)097
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DOI: https://doi.org/10.1007/JHEP10(2014)097