High-energy QCD dynamics from bottom flavor fragmentation at the Hi-Lumi LHC

Abstract

We study the inclusive production of hadrons with bottom flavor at the LHC and its luminosity upgrade. We describe the collinear fragmentation of singly $b$-flavored hadrons, $B$ mesons and $Λ_b$ baryons, via the KKSS07 determination of fragmentation functions, while for charmed $B$ mesons, $B_c(^1S_0)$ and $B_c(^3S_1)$ particles, we employ the novel ZCFW22 set, built on the basis of state-of-the-art nonrelativistic QCD inputs. We use the JETHAD multimodular working environment to analyze rapidity and transverse-momentum distributions for observables sensitive to the associated emission of two hadrons or a hadron-plus-jet system. Our reference formalism is the NLL/NLO$^+$ hybrid collinear and high-energy factorization, where the standard collinear description is improved by the inclusions of energy logarithms resummed up to the next-to-leading approximation and beyond. We provide a corroborating evidence that $b$-flavor emissions act as fair stabilizers of the high-energy resummation, thus serving as valuable tools for precision studies of high-energy QCD. As a bonus, we highlight that the predicted production-rate hierarchy between noncharmed $b$-hadrons and charmed $B_c(^1S_0)$ mesons is in line with recent LHCb estimates. This serves as simultaneous benchmark both for the hybrid factorization and for the single-parton fragmentation mechanism based on initial-scale inputs calculated via the nonrelativistic QCD effective theory.