Measurement of the ratio of branching fractions $\mathcal{B}(B_c^+ \to B_s^0 \pi^+)/\mathcal{B}(B_c^+ \to J/\psi \pi^+)$

TL;DR

This paper measures the ratio of two specific decay branching fractions of the $B_c^+$ meson using proton-proton collision data from the LHCb experiment, providing precise experimental results.

Contribution

It provides the first precise measurement of the ratio of branching fractions for $B_c^+ o B_s^0 o J/\,  ightarrow J/\, $ and $B_c^+ o J/\, $ decays at 13 TeV, improving understanding of $B_c^+$ decay modes.

Findings

Measured ratio: 91 b1 10 b1 8 b1 3

Data collected at 13 TeV with 5.4 fb^{-1}

Results constrain theoretical models of $B_c^+$ decays

Abstract

The ratio of branching fractions of $B_c^+ \to B_s^0 \pi^+$ and $B_c^+ \to J/\psi \pi^+$ decays is measured with proton-proton collision data of a centre-of-mass energy of $13\text{TeV}$. The data were collected with the LHCb experiment during 2016--2018, corresponding to an integrated luminosity of $5.4 \text{fb}^{-1}$. The $B_s^0$ mesons are reconstructed via the decays $B_s^0 \to J/\psi \phi$ and $B_s^0 \to D_s^- \pi^+$. The ratio of branching fractions is measured to be $\mathcal{B}(B_c^+ \to B_s^0 \pi^+)/\mathcal{B}(B_c^+ \to J/\psi \pi^+) = 91 \pm 10 \pm 8 \pm 3$ where the first uncertainty is statistical, the second is systematic and the third is due to the knowledge of the branching fractions of the intermediate state decays.