QCD field-strength correlators on a Polyakov loop with gradient flow at next-to-leading order

TL;DR

This paper analyzes how gradient flow affects QCD field-strength correlators along a Polyakov loop at next-to-leading order, establishing a renormalization matching crucial for lattice QCD studies of heavy quark momentum diffusion.

Contribution

It provides a next-to-leading order perturbative analysis of gradient flow renormalization for field-strength correlators in QCD, linking lattice measurements to continuum physics.

Findings

Gradient flow renormalizes correlators at next-to-leading order.

Established a matching between lattice and continuum correlators.

Facilitates nonperturbative studies of heavy quark momentum diffusion.

Abstract

Momentum exchange between a heavy quark and a hot quark-gluon medium can be characterized nonperturbatively in terms of field-strength field-strength (E-E and B-B) correlators along a Polyakov loop. These can be studied on the lattice and analytically continued. However the lattice typically determines the correlators after the application of gradient flow. We investigate how gradient flow renormalizes these correlation functions by carrying out a next-to-leading order perturbative analysis of the correlators including gradient flow. This establishes a next-to-leading order renormalization matching between the correlators as measured on the lattice and the correlators relevant for momentum diffusion.