Orateurs
Description
The exclusive decay channels $\mathrm{B}_{\mathrm{s}}^{0}\to \mathrm{J}/\psi \phi$ and $\mathrm{B}^{+}\to\mathrm{J}/\psi K^{+}$ are investigated. The differential cross sections of $\mathrm{B}_{\mathrm{s}}^{0}$ and $\mathrm{B}^+$ mesons as a function of their transverse momenta ($p_\mathrm{T}$) in proton-proton collisions at 5.02 TeV are well-described by fixed-order plus next-to-leading logarithm calculations, using an integrated luminosity of 302.3 pb$^{-1}$. By utilizing previous lead-lead collision data at the same nucleon-nucleon (NN) center of mass energy, $R_{\mathrm{AA}}$ factors for the B mesons are determined. Additionally, the measurement of the $\mathrm{B}^+$ meson production cross section is presented with respect to meson $p_\mathrm{T}$ inclusively and, for the first time, in different charged particle multiplicity ranges. This study is conducted in proton-lead collisions at NN center-of-mass energy of $8.16~\mathrm{TeV}$, utilizing data collected by the CMS detector in 2016 with an integrated luminosity of 175 nb$^{-1}$. The analysis focuses on the exclusive decay channel $\mathrm{B}^{+}\to \mathrm{J}/\psi K^{+}$. Inclusive results demonstrate good agreement with fixed-order next-to-leading log calculations, and the ratio of nuclear modification factors is measured for different charged particle multiplicities. These studies provide a comprehensive understanding of $\mathrm{B}_{\mathrm{s}}^{0}$ and $\mathrm{B}^+$ meson production, shedding light on their behavior in different collision environments and offering insights into the nuclear modification factors associated with these mesons.
