Measurements of charm mixing and CP violation parameters from the decay-time-dependent ratio of D0âK+Ï- to D0âK-Ï+ decay rates and the charge-conjugate ratio are reported. The analysis uses B-âDâ+μ-X, and charge-conjugate decays, where Dâ+âD0Ï+, and D0âKϱ. The pp collision data are recorded by the LHCb experiment at center-of-mass energies s=7 and 8 TeV, corresponding to an integrated luminosity of 3 fb-1. The data are analyzed under three hypotheses: (i) mixing assuming CP symmetry, (ii) mixing assuming no direct CP violation in the Cabibbo-favored or doubly Cabibbo-suppressed decay amplitudes, and (iii) mixing allowing either direct CP violation and/or CP violation in the superpositions of flavor eigenstates defining the mass eigenstates. The data are also combined with those from a previous LHCb study of D0âKÏ decays from a disjoint set of Dâ+ candidates produced directly in pp collisions. In all cases, the data are consistent with the hypothesis of CP symmetry.
Measurements of charm mixing and CP violation using D0→K±π∓ decays
De Serio, M.;Pappagallo, M.;
2017-01-01
Abstract
Measurements of charm mixing and CP violation parameters from the decay-time-dependent ratio of D0âK+Ï- to D0âK-Ï+ decay rates and the charge-conjugate ratio are reported. The analysis uses B-âDâ+μ-X, and charge-conjugate decays, where Dâ+âD0Ï+, and D0âKϱ. The pp collision data are recorded by the LHCb experiment at center-of-mass energies s=7 and 8 TeV, corresponding to an integrated luminosity of 3 fb-1. The data are analyzed under three hypotheses: (i) mixing assuming CP symmetry, (ii) mixing assuming no direct CP violation in the Cabibbo-favored or doubly Cabibbo-suppressed decay amplitudes, and (iii) mixing allowing either direct CP violation and/or CP violation in the superpositions of flavor eigenstates defining the mass eigenstates. The data are also combined with those from a previous LHCb study of D0âKÏ decays from a disjoint set of Dâ+ candidates produced directly in pp collisions. In all cases, the data are consistent with the hypothesis of CP symmetry.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.