Using a pp collision data sample corresponding to an integrated luminosity of 3.0 fb-1, collected by the LHCb detector, we present the first search for the strangeness-changing weak decay Ξb-→Λb0π-. No b hadron decay of this type has been seen before. A signal for this decay, corresponding to a significance of 3.2 standard deviations, is reported. The relative rate is measured to be fΞb-fΛb0B(Ξb-→Λb0π-)=(5.7±1.8-0.9+0.8)×10-4,where fΞb- and fΛb0 are the b→Ξb- and b→Λb0 fragmentation fractions, and B(Ξb-→Λb0π-) is the branching fraction. Assuming fΞb-/fΛb0 is bounded between 0.1 and 0.3, the branching fraction B(Ξb-→Λb0π-) would lie in the range from (0.57±0.21)% to (0.19±0.07)%. © 2015 CERN, for the LHCb Collaboration. Published by the American Physical Society under the terms of the »http://creativecommons.org/licenses/by/3.0/» Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.
Evidence for the Strangeness-Changing Weak Decay Ξb- → Λb0 π-
PALANO, Antimo;PAPPAGALLO, MARCO IGNAZIO;
2015-01-01
Abstract
Using a pp collision data sample corresponding to an integrated luminosity of 3.0 fb-1, collected by the LHCb detector, we present the first search for the strangeness-changing weak decay Ξb-→Λb0π-. No b hadron decay of this type has been seen before. A signal for this decay, corresponding to a significance of 3.2 standard deviations, is reported. The relative rate is measured to be fΞb-fΛb0B(Ξb-→Λb0π-)=(5.7±1.8-0.9+0.8)×10-4,where fΞb- and fΛb0 are the b→Ξb- and b→Λb0 fragmentation fractions, and B(Ξb-→Λb0π-) is the branching fraction. Assuming fΞb-/fΛb0 is bounded between 0.1 and 0.3, the branching fraction B(Ξb-→Λb0π-) would lie in the range from (0.57±0.21)% to (0.19±0.07)%. © 2015 CERN, for the LHCb Collaboration. Published by the American Physical Society under the terms of the »http://creativecommons.org/licenses/by/3.0/» Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.