Measurement of the branching fraction ratio B (Bc+→ψ (2 S )π+)/B (Bc+→J /ψ π+)

Abstract

Using pp collision data collected by LHCb at center-of-mass energies √ s = 7 TeV and 8 TeV, corresponding to an integrated luminosity of 3 fb−1 , the ratio of the branching fraction of the B+ c → ψ(2S)π + decay relative to that of the B+ c → J/ψ π+ decay is measured to be 0.268 ± 0.032 (stat) ± 0.007 (syst) ± 0.006 (BF). The first uncertainty is statistical, the second is systematic, and the third is due to the uncertainties on the branching fractions of the J/ψ → µ +µ − and ψ(2S) → µ +µ − decays. This measurement is cons