Line defects and radiation in $\mathcal{N}=2$ theories

TL;DR

This paper investigates the conformal data of superconformal line defects in 4D $ =2$ theories, establishing a universal relation between stress tensor one-point functions and displacement operator two-point functions, with implications for energy emission in gauge theories.

Contribution

It proves a theory-independent relation linking stress tensor and displacement operator correlators in superconformal line defects, providing new insights into defect dynamics and radiation.

Findings

Derived a universal relation between stress tensor and displacement operator correlators.

Connected Bremsstrahlung energy emission to stress tensor coupling for charged particles.

Enhanced understanding of defect conformal data in $ =2$ supersymmetric theories.

Abstract

We study the conformal data of a generic superconformal half-BPS line defect in a four-dimensional $\mathcal{N} = 2$ theory. We prove a theory independent relation between the one-point function of the stress tensor in the presence of the line defect and the two-point function of the displacement operator. When the defect is interpreted as a heavy charged particle in a gauge theory, the result relates the energy emitted through Bremsstrahlung with the coupling of the stress tensor to the particle at rest.