# Measurement of the cross section for inclusive isolated-photon production in $pp$ collisions at $\sqrt s=13$ TeV using the ATLAS detector

## TL;DR

This paper measures the production rate of isolated photons in proton-proton collisions at 13 TeV using ATLAS, comparing results with theoretical predictions to test quantum chromodynamics models.

## Contribution

First measurement of inclusive isolated-photon cross sections at 13 TeV with detailed comparison to NLO QCD and Monte Carlo predictions.

## Key findings

- NLO QCD and Monte Carlo models adequately describe the data.
- Photon cross sections measured as a function of transverse energy and pseudorapidity.
- Results provide constraints for theoretical models of photon production.

## Abstract

Inclusive isolated-photon production in $pp$ collisions at a centre-of-mass energy of 13 TeV is studied with the ATLAS detector at the LHC using a data set with an integrated luminosity of 3.2 fb$^{-1}$. The cross section is measured as a function of the photon transverse energy above 125 GeV in different regions of photon pseudorapidity. Next-to-leading-order perturbative QCD and Monte Carlo event-generator predictions are compared to the cross-section measurements and provide an adequate description of the data.