Charm meson oscillations are observed in a time-dependent analysis of the ratio of D0âK+Ï-Ï+Ï- to D0âK-Ï+Ï-Ï+ decay rates, using data corresponding to an integrated luminosity of 3.0 fb-1 recorded by the LHCb experiment. The measurements presented are sensitive to the phase-space averaged ratio of doubly Cabibbo-suppressed to Cabibbo-favored amplitudes rDK3Ï and the product of the coherence factor RDK3Ï and a charm mixing parameter yK3Ïâ². The constraints measured are rDK3Ï=(5.67±0.12)Ã10-2, which is the most precise determination to date, and RDK3ÏyK3Ïâ²=(0.3±1.8)Ã10-3, which provides useful input for determinations of the CP-violating phase γ in B±âDK±, DâKϱÏϱ decays. The analysis also gives the most precise measurement of the D0âK+Ï-Ï+Ï- branching fraction, and the first observation of D0-D-0 oscillations in this decay mode, with a significance of 8.2 standard deviations.
First Observation of D-0 - (D)over-bar(0) Oscillations in D-0 -> K+pi(-)pi(+)pi(-) Decays and Measurement of the Associated Coherence Parameters
COGONI, VIOLETTA;Dettori, F.;Lai, A.;MANCA, GIULIA;OLDEMAN, RUDOLF GERHARD CHRISTIAAN;SAITTA, BIAGIO;VACCA, CLAUDIA;
2016-01-01
Abstract
Charm meson oscillations are observed in a time-dependent analysis of the ratio of D0âK+Ï-Ï+Ï- to D0âK-Ï+Ï-Ï+ decay rates, using data corresponding to an integrated luminosity of 3.0 fb-1 recorded by the LHCb experiment. The measurements presented are sensitive to the phase-space averaged ratio of doubly Cabibbo-suppressed to Cabibbo-favored amplitudes rDK3Ï and the product of the coherence factor RDK3Ï and a charm mixing parameter yK3Ïâ². The constraints measured are rDK3Ï=(5.67±0.12)Ã10-2, which is the most precise determination to date, and RDK3ÏyK3Ïâ²=(0.3±1.8)Ã10-3, which provides useful input for determinations of the CP-violating phase γ in B±âDK±, DâKϱÏϱ decays. The analysis also gives the most precise measurement of the D0âK+Ï-Ï+Ï- branching fraction, and the first observation of D0-D-0 oscillations in this decay mode, with a significance of 8.2 standard deviations.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.