A fragmentation-based study of heavy quark production

TL;DR

This paper examines the limitations of common approximations in heavy quark production at the LHC, emphasizing the importance of resumming collinear logarithms for accurate predictions, especially in exclusive observables.

Contribution

It introduces a perturbative fragmentation-function approach to highlight the necessity of resumming collinear logarithms in heavy quark production calculations.

Findings

Neglecting collinear logarithm resummation can lead to inaccurate predictions.

Resummation schemes improve the accuracy of heavy quark production models.

Exclusive observables are particularly sensitive to collinear effects.

Abstract

Processes involving heavy quarks are a crucial component of the LHC physics program, both by themselves and as backgrounds for Higgs physics and new physics searches. In this work, we critically reconsider the validity of the widely-adopted approximation in which heavy quarks are generated at the matrix-element level, with special emphasis on the impact of the collinear logarithms associated with final-state heavy quark and gluon splittings. Our study, based on a perturbative fragmentation-function approach, explicitly shows that neglecting the resummation of collinear logarithms may yield inaccurate predictions, in particular when observables exclusive in the heavy quark degrees of freedom are considered. Our findings motivate the use of schemes which encompass the resummation of final-state collinear logarithms.