Measurement of the dependence of the hadron production fraction ratios f_s / f_u and f_d / f_u on B meson kinematic variables in proton-proton collisions at sqrt{s) = 13 TeV

The dependence of the ratio between the B 0 s and B þ hadron production fractions, f s =f u , on the transverse momentum (p T ) and rapidity of the B mesons is studied using the decay channels B 0 s → J=ψφ and B þ → J=ψK þ . The analysis uses a data sample of proton-proton collisions at a center-of-mass energy of 13 TeV, collected by the CMS experiment in 2018 and corresponding to an integrated luminosity of 61.6 fb −1 . The f s =f u ratio is observed to depend on the B pT and to be consistent with becoming asymptotically constant at large p T . No rapidity dependence is observed. The ratio of the B 0 to B þ meson production fractions, f d =f u , is also measured, for the first time in proton-proton collisions, using the B 0 → J=ψK "0 decay channel. The result is found to be within 1 standard deviation of unity and independent of p T and rapidity, as expected from isospin invariance