The first observation of the decays anti-B0s → Ds+ K− π+ π− and anti-B0 → Ds+ K− π+ π− are reported using an integrated luminosity of 1.0 fb^−1 recorded by the LHCb experiment. The branching fractions, normalized with respect to anti-B0s → Ds+ π− π+ π− and anti-B0s → Ds+ K− π+ π−, respectively, are measured to be B(anti-B0s → Ds+ K− π+ π−)/B(anti-B0s → Ds+ π− π+ π−) = (5.2 ± 0.5 ± 0.3) x 10^−2 and B(anti-B0 → Ds+ K− π+ π−)/B(anti-B0s → Ds+ K− π+ π−) = 0.54 ± 0.07 ± 0.07, where the first uncertainty is statistical and the second is systematic. The anti-B0s → Ds+ K− π+ π− decay is of particular interest as it can be used to measure the weak phase γ. First observation of the anti-B0s → Ds1(2536)+ π−, Ds1+ → Ds+ π− π+ decay is also presented, and its branching fraction relative to anti-B0s → Ds+ π− π+ π− is found to be B(anti-B0s → Ds1(2536)+ π−, Ds1+ → Ds+ π− π+)/B(anti-B0s → Ds+ π− π+ π−) = (4.0 ± 1.0 ± 0.4) x 10^−3.
First Observation of the Decays anti-B0(s) → Ds+ K− π+ π− and anti-B0s → Ds1(2536)+ π−
CARBONE, ANGELO;GALLI, DOMENICO;PATRIGNANI, CLAUDIA;PERAZZINI, STEFANO;VAGNONI, VINCENZO MARIA;ZANGOLI, MARIA;
2012
Abstract
The first observation of the decays anti-B0s → Ds+ K− π+ π− and anti-B0 → Ds+ K− π+ π− are reported using an integrated luminosity of 1.0 fb^−1 recorded by the LHCb experiment. The branching fractions, normalized with respect to anti-B0s → Ds+ π− π+ π− and anti-B0s → Ds+ K− π+ π−, respectively, are measured to be B(anti-B0s → Ds+ K− π+ π−)/B(anti-B0s → Ds+ π− π+ π−) = (5.2 ± 0.5 ± 0.3) x 10^−2 and B(anti-B0 → Ds+ K− π+ π−)/B(anti-B0s → Ds+ K− π+ π−) = 0.54 ± 0.07 ± 0.07, where the first uncertainty is statistical and the second is systematic. The anti-B0s → Ds+ K− π+ π− decay is of particular interest as it can be used to measure the weak phase γ. First observation of the anti-B0s → Ds1(2536)+ π−, Ds1+ → Ds+ π− π+ decay is also presented, and its branching fraction relative to anti-B0s → Ds+ π− π+ π− is found to be B(anti-B0s → Ds1(2536)+ π−, Ds1+ → Ds+ π− π+)/B(anti-B0s → Ds+ π− π+ π−) = (4.0 ± 1.0 ± 0.4) x 10^−3.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.