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The hadrochemistry of bottom quarks (b) produced in hadronic collisions encodes valuable information on the mechanism of color neutralization in these reactions. Since the b-quark mass is much larger than the typical hadronic scale of 1 GeV, bbar pair production is expected to be well separated from subsequent hadronization processes. A significantly larger fraction of b baryons has been observed in proton-proton (pp) and proton-antiproton (pbarp) reactions relative to eþe2 collisions, challenging theoretical descriptions. We address this problem by employing a statistical hadronization approach with an augmented set of b-hadron states beyond currently measured ones, guided by the relativistic quark model and lattice-QCD computations. Assuming relative chemical equilibrium between different b-hadron yields, thermal densities are used as fragmentation weights of b quarks into various hadron species. With quark model estimates of the decay patterns of excited states, the fragmentation fractions of weakly decaying b hadrons are computed and found to agree with measurements in pbarp collisions at the Tevatron. By combining transverse-momentum (pT) distributions of b quarks from perturbative QCD with thermal weights and independent fragmentation toward high pT, a fair description of the pT-dependent B-meson ratios measured in pp collisions at the LHC is obtained. The observed enhancement of Lambda_b attributed to the feeddown from thus far unobserved excited b baryons. Finally, we implement the hadrochemistry into a strongly coupled transport approach for b quarks in heavy-ion collisions, utilizing previously determined b-quark transport coefficients in the quark-gluon plasma, to highlight the modifications of hadrochemistry and collective behavior of b hadrons in Pb-Pb collisions at the LHC. 

Heavy-flavor hadrons produced in ultrarelativistic heavy-ion collisions are a sensitive probe for studying hadronization mechanisms of the quark-gluon-plasma. In this paper, we survey how different transport models for the simulation of heavy-quark diffusion through a quark-gluon plasma in heavy-ion collisions implement hadronization and how this affects final state observables. Utilizing the same input charm-quark distribution in all models at the hadronization transition, we find that the transverse-momentum dependence of the nuclear modification factor of various charm hadron species has significant sensitivity to the hadronization scheme. In addition, the charm-hadron elliptic flow exhibits a nontrivial dependence on the elliptic flow of the hadronizing partonic medium. 

We deploy a kinetic-rate equation to evaluate the transport of J /ψ, ψ(2 S ), B c and X (3872) in ultrarelativistic heavy-ion collisions and compare their production yields to experimental data from the Large Hadron Collider. The rate equation has two main transport parameters: the equilibrium limit and reaction rate for each state. The temperature-dependent equilibrium limits include charm- and bottom-quark fugacities based on their initial production. The reaction rates for charmonia, bottomonia and B c rely on charm- and bottomquark masses and binding energies from a thermodynamic T -matrix approach. For the X (3872) particle, internal structure information is encoded in reaction rates and initial conditions in the hadronic phase via two different scenarios: a loosely bound hadronic molecule vs. a compact tetraquark.