Event engineering studies for heavy flavor production and hadronization in high multiplicity hadron-hadron and hadron-nucleus collisions

TL;DR

This paper uses the Color Glass Condensate effective field theory combined with NRQCD and fragmentation functions to study heavy flavor production in high multiplicity collisions, revealing rapid growth in certain quarkonium states.

Contribution

It introduces a novel combined theoretical framework for event engineering in heavy flavor production, matching experimental data and revealing new insights into hadronization mechanisms.

Findings

Excellent agreement with LHC data in high multiplicity events

Rapid growth of $^3S_1^{[8]}$ state fragmentation in rare events

Validation of CGC+NRQCD approach for heavy flavor studies

Abstract

Heavy flavor measurements in high multiplicity proton-proton and proton-nucleus collisions at collider energies enable unique insights into their production and hadronization mechanism because experimental and theoretical uncertainties cancel in ratios of their cross-sections relative to minimum bias events. We explore such event engineering using the Color Glass Condensate (CGC) effective field theory to compute short distance charmonium cross-sections. The CGC is combined with heavy-quark fragmentation functions to compute $D$-meson cross-sections; for the $J/\psi$, hadronization is described employing Nonrelativistic QCD (NRQCD) and an Improved Color Evaporation model. Excellent agreement is found between the CGC computations and the LHC heavy flavor data in high multiplicity events. Event engineering in this CGC+NRQCD framework reveals a very rapid growth in the fragmentation of the $^3S_1^{[8]}$ state in rare events relative to minimum bias events.