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arXiv · 2401.00738

Bottom-hadron production in high-energy $pp$ and heavy-ion collisions

Min He
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Abstract

The hadro-chemistry of bottom quarks produced in hadronic collisions encodes valuable information on the mechanism of color-neutralization in these reactions. We first compute the chemistry of bottom-hadrons in high-energy $pp$ collisions employing statistical hadronization with a largely augmented set of states beyond the currently measured spectrum. This enables a comprehensive prediction of fragmentation fractions of weakly decaying bottom hadrons for the first time and a satisfactory explanation of the existing measurements in $pp$ collisions at the LHC. Utilizing the bottom hadro-chemistry thus obtained as the baseline, we then perform transport simulations of bottom quarks in the hot QCD matter created in PbPb collisions at the LHC energy and calculate the pertinent bottom-hadron observables. The transverse momentum ($p_T$) dependent modifications of the bottom baryon-to-meson ratio ($\Lambda_b^0/B^-$) relative to their $pp$ counterparts are highlighted as a result of bottom quark diffusion and hadronization in the Quark-Gluon Plasma (QGP). We finally summarize the heavy quark (charm vs bottom) diffusion coefficients as extracted from transport simulations and compare them to result from recent full lattice QCD computations.

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Min He. 2024-01-01. Bottom-hadron production in high-energy $pp$ and heavy-ion collisions. https://arxiv.org/abs/2401.00738

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