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The dependence of the ratio between the Bs(0) and B+ 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-s(0) -> J/ψϕ and B+ -> J/ψ K+. 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 p(T) 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+ meson production fractions, f(d)/f(u), is also measured, for the first time in proton-proton collisions, using the B-0 -> J/ψ K*(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.
Jan Steggemann, Konstantin Androsov, Anna Mascellani, Joanna Malgorzata Wanczyk
Olivier Schneider, Aurelio Bay, Guido Haefeli, Tatsuya Nakada, Frédéric Blanc, Lesya Shchutska, Elena Graverini, Donal Patrick Hill, Marie Theres Christin Bachmayer, Sebastian Schulte, Aravindhan Venkateswaran, Veronica Sølund Kirsebom, Renato Quagliani, Lino Ferreira Lopes, Luis Miguel Garcia Martin, Vitalii Lisovskyi, Surapat Ek-In, Serhii Cholak, Federico Ronchetti, Sara Celani, Anni Matilda Kauniskangas, Raphaël van Laak, Maarten Willibrord Uriël Van Dijk, Ettore Zaffaroni, Elisabeth Maria Niel, Brianna Leililani Thielen, Yifei Song, Dimitrios Kaminaris