Heavy Quark Pair Energy Correlators: From Profiling Partonic Splittings to Probing Heavy-Flavor Fragmentation

TL;DR

This paper introduces heavy-flavor energy correlators as a new observable to analyze partonic splittings and heavy-flavor fragmentation, with applications in probing medium effects in high-energy collisions.

Contribution

It develops the collinear factorization and resummation of heavy-flavor energy correlators, demonstrating their sensitivity to heavy-quark pair splittings and medium modifications.

Findings

Sensitive to heavy-quark pair splitting functions

Capable of probing medium-induced modifications

Reveals medium's spatial structure effects

Abstract

We introduce heavy-flavor energy correlators, $\langle \Psi |\mathcal{E}_{\mathcal{H}}(\vec{n}_1) \mathcal{E}_{\mathcal{H}}(\vec{n}_2)|\Psi \rangle$, as a powerful observable for profiling partonic splittings and characterizing heavy-flavor fragmentation. We present its collinear factorization, perform resummation, and demonstrate the angular distribution's sensitivity to both the heavy-quark pair splitting and their subsequent fragmentation. We then apply the heavy-flavor EEC to probe medium-induced effects, revealing its sensitivity to medium modifications to heavy-quark pair splitting functions and to the medium's spatial structure.