Differential Heavy Quark Distributions and Correlations in Longitudinally Polarized Deep-Inelastic Scattering

TL;DR

This paper calculates the heavy flavor contribution to polarized deep-inelastic scattering structure functions at next-to-leading order, using a new Monte Carlo generator to study heavy quark distributions and correlations relevant for future Electron-Ion Collider experiments.

Contribution

It introduces the first NLO calculation of heavy quark distributions in polarized DIS with a novel Monte Carlo tool for detailed observables and correlations.

Findings

Significant double-spin asymmetries predicted for heavy quark production.

Sensitivity of heavy quark observables to the gluon helicity distribution.

Theoretical uncertainties from scale choices are analyzed.

Abstract

We present a first calculation of the heavy flavor contribution to the longitudinally polarized deep-inelastic scattering structure function $g_1^{Q}$, differential in the transverse momentum or the rapidity of the observed heavy quark $Q$ or antiquark $\overline Q$. All results are obtained at next-to-leading order accuracy in QCD within the framework of a newly developed parton-level Monte Carlo generator that also allows one to study observables associated with the produced heavy quark pair such as its invariant mass distribution or its correlation in azimuthal angle. First phenomenological studies are carried out for various heavy quark distributions in a kinematic regime relevant for a future Electron-Ion Collider with a particular emphasis on the expected size of the corresponding double-spin asymmetries and their sensitivity to the still poorly constrained helicity gluon distribution. Theoretical uncertainties associated with the choice of the factorization scale are discussed for selected observables.