An analysis of B+→K0Sπ+ and B+→K0SK+ decays is performed with the LHCb experiment. The pp collision data used correspond to integrated luminosities of 1fb−1 and 2fb−1 collected at centre-of-mass energies of s√=7TeV and s√=8TeV, respectively. The ratio of branching fractions and the direct {\it CP} asymmetries are measured to be B(B+→K0SK+)/B(B+→K0Sπ+)=0.064±0.009(stat.)±0.004(syst.), ACP(B+→K0Sπ+)=−0.022±0.025(stat.)±0.010(syst.) and ACP(B+→K0SK+)=−0.21±0.14(stat.)±0.01(syst.). The data sample taken at s√=7TeV is used to search for B+c→K0SK+ decays and results in the upper limit (fc⋅B(B+c→K0SK+))/(fu⋅B(B+→K0Sπ+))<5.8×10−2at 90% confidence level, where fc and fu denote the hadronisation fractions of a bˉ quark into a B+c or a B+ meson, respectively.
Branching fraction and CP asymmetry of the decays B+→K0Sπ+ and B+→K0SK+
AURIEMMA, Giulio;SATRIANO, Celestina;
2013-01-01
Abstract
An analysis of B+→K0Sπ+ and B+→K0SK+ decays is performed with the LHCb experiment. The pp collision data used correspond to integrated luminosities of 1fb−1 and 2fb−1 collected at centre-of-mass energies of s√=7TeV and s√=8TeV, respectively. The ratio of branching fractions and the direct {\it CP} asymmetries are measured to be B(B+→K0SK+)/B(B+→K0Sπ+)=0.064±0.009(stat.)±0.004(syst.), ACP(B+→K0Sπ+)=−0.022±0.025(stat.)±0.010(syst.) and ACP(B+→K0SK+)=−0.21±0.14(stat.)±0.01(syst.). The data sample taken at s√=7TeV is used to search for B+c→K0SK+ decays and results in the upper limit (fc⋅B(B+c→K0SK+))/(fu⋅B(B+→K0Sπ+))<5.8×10−2at 90% confidence level, where fc and fu denote the hadronisation fractions of a bˉ quark into a B+c or a B+ meson, respectively.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
