# Observation of Bs 0 mesons and measurement of the Bs 0/B+ yield ratio in PbPb collisions at [Formula presented] TeV

The CMS collaboration

## 摘要

The Bs 0 and B+ production yields are measured in PbPb collisions at a center-of-mass energy per nucleon pair of 5.02 TeV. The data sample, collected with the CMS detector at the LHC, corresponds to an integrated luminosity of 1.7 nb−1. The mesons are reconstructed in the exclusive decay channels B→s0J/ψ(μ+μ)ϕ(K+K) and B→+J/ψ(μ+μ)K+, in the transverse momentum range 7–50 GeV/c and absolute rapidity 0–2.4. The Bs 0 meson is observed with a statistical significance in excess of five standard deviations for the first time in nucleus-nucleus collisions. The measurements are performed as functions of the transverse momentum of the B mesons and of the PbPb collision centrality. The ratio of production yields of Bs 0 and B+ is measured and compared to theoretical models that include quark recombination effects.

原文 ???core.languages.en_GB??? 137062 Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 829 https://doi.org/10.1016/j.physletb.2022.137062 已出版 - 10 6月 2022