Measurement of $f_s\mathrm{/}{f}_u$ variation with proton-proton collision energy and $B$-meson kinematics

The ratio of the ${\mathrm{B}}_{\mathrm{s}}^0$ and ${\mathrm{B}}^{+}$ fragmentation fractions $f_{\mathrm{s}}$ and $f_u$ is studied with $B_{\mathrm{s}}^0\to \mathrm{J}\mathrm{/}\psi \varphi$ and $B^{+}\to \mathrm{J}\mathrm{/}\psi K^{+}$ decays using data collected by the LHCb experiment in proton-proton collisions at 7, 8 and 13$\text{ TeV}$ center-of-mass energies. The analysis is performed in bins of $\mathrm{B}$-meson momentum, longitudinal momentum, transverse momentum, pseudorapidity and rapidity. The fragmentation-fraction ratio $f_$\mathrm{s}$ / f_u$isobservedtodependonthe$$\mathrm{B}$$-meson transverse momentum with a significance of $6.0\sigma$. This dependency is driven by the 13$\text{ TeV}$ sample ($8.7\sigma$) while the results for the other collision energies are not significant when considered separately. Furthermore the results show a $4.8\sigma$ evidence for an increase of $f_{\mathrm{s}}\mathrm{/}{f}_u$ as a function of collision energy.