# Transverse-momentum resummation for the signal-background interference in the $H \to \gamma\gamma$ channel at the LHC

## TL;DR

This paper improves the calculation of Higgs to diphoton signal-background interference at the LHC by including next-to-leading order QCD corrections and transverse-momentum resummation, crucial for accurate predictions at low transverse momentum.

## Contribution

It provides an upgraded, more precise calculation of interference effects in Higgs diphoton decays, incorporating NLO QCD and $q_T$ resummation at NLL accuracy.

## Key findings

- Interference effects are significant at low $q_T$ regions.
- Resummation improves the reliability of the theoretical predictions.
- The study highlights the importance of higher-order corrections for accurate Higgs measurements.

## Abstract

We present an upgraded calculation of the effects of resonance-continuum interference for the Higgs boson decaying to two photons at the Large Hadron Collider, at next-to-leading order in the strong coupling $\alpha_S$, $O(\alpha_S^3)$, and including transverse-momentum ($q_T$) resummation at next-to-leading logarithmic accuracy. We study the importance of the interference contribution in different transverse-momentum regions, with a particular focus on the low $q_T$ region $q_T^2 << Q^2$ (with $Q^2$ being the invariant diphoton mass) where resummation becomes essential for a reliable calculation.