# Probing the photonic content of the proton using photon-induced dilepton production in $p+\textrm{Pb}$ collisions at the LHC

## TL;DR

This paper introduces a novel experimental approach to measure the photon content of the proton at LHC energies using dilepton production in proton-lead collisions, providing a cleaner environment for probing the photon PDF.

## Contribution

It proposes a new method based on photon-induced dilepton production in p+Pb collisions to directly measure the photon PDF inside the proton at LHC energies.

## Key findings

- Calculated cross sections using collinear photon PDFs.
- Identified optimal scale choices for the process.
- Estimated event rates for existing LHC data.

## Abstract

We propose a new experimental method to probe the photon parton distribution function inside the proton (photon PDF) at LHC energies. The method is based on the measurement of dilepton production from the $\gamma p\rightarrow\ell^+\ell^-+X$ reaction in proton--lead collisions. These experimental conditions guarantee a clean environment, both in terms of reconstruction of the final state and in terms of possible background. We firstly calculate the cross sections for this process with collinear photon PDFs, where we identify optimal choice of the scale, in analogy to deep inelastic scattering kinematics. We then perform calculations including the transverse-momentum dependence of the probed photon. Finally we estimate rates of the process for the existing LHC data samples.