The thermal dilepton rate at NLO at small and large invariant mass

TL;DR

This paper presents a next-to-leading order calculation of the dilepton production rate in hot QCD plasma across different invariant mass regimes, improving the theoretical understanding relevant for experimental measurements.

Contribution

It generalizes previous photon rate calculations to small invariant mass dileptons and merges low- and high-mass results for a comprehensive NLO-accurate rate.

Findings

NLO dilepton rate determined for small invariant mass.

Merged low- and high-mass NLO results into a unified rate.

Implications for photon rate extraction from dilepton data.

Abstract

We report on a recent next-to-leading order perturbative determination of the dilepton rate from a hot QCD plasma for frequency and momentum of the order of the temperature and for much smaller invariant mass $M\sim gT$. We briefly review the calculation, which generalizes the previous one for the photon case ($M=0$). We then analyze the consequences of the new calculation for the extraction of the photon rate from the small mass dilepton measurements. We then review a recent NLO determination at large $M$ and we show how to match and merge its results with the low-mass ones, resulting in a single rate which is NLO-accurate over the phenomenologically relevant region.