Measurement of B meson production fraction ratios in proton-proton collisions at √s = 13 TeV using open-charm and charmonium decays

Production fraction ratios of 𝐵⁺, 𝐵⁰, and 𝐵⁰_𝑠 mesons are measured in proton-proton collisions at √𝑠=13 TeV using a special dataset recorded in 2018 with high-rate triggers designed to collect an unbiased sample of 1⁢010 𝑏 hadrons with the CMS experiment at the LHC. These data allow the study of the open-charm decays of 𝐵 mesons (𝐵(𝑠) →𝜋⁢𝐷(𝑠)) where the 𝐷 meson decays into fully hadronic final states. By utilizing known branching fractions and precise theoretical calculations, production fraction ratios as functions of 𝐵 meson transverse momentum (𝑝T) and rapidity (𝑦) are measured using open-charm decays in the kinematic range of 8<𝑝T<60 GeV and |𝑦| <2.25. In addition, the same dataset is used to measure the relative production fraction ratios with the charmonium decay channels [𝐵(𝑠) →𝑋⁢𝐽/𝜓 with 𝑋 indicating a 𝐾⁺, 𝐾*(892)⁰, or 𝜙⁡(1020) meson] where the 𝐽/𝜓 meson decays into a pair of muons. The open-charm results are used to normalize the relative production fraction ratios obtained from the charmonium samples. Measurements of the ratios of branching fractions of 𝐵 meson decays to charmonium and open-charm final states are also reported, which will improve the world-average values of these ratios. Finally, we test isospin invariance in 𝐵 meson production in proton-proton collisions and observe that it holds within the experimental precision.