# Monopole production via photon fusion at the LHC

## TL;DR

This paper investigates the production of magnetic monopoles via photon fusion at the LHC, providing new cross-section calculations and simulation tools to aid experimental searches for monopoles.

## Contribution

It introduces a perturbative approach to monopole production cross sections via photon fusion, including implementation into MadGraph models for LHC searches.

## Key findings

- Cross sections for monopoles of various spins are calculated.
- A new implementation for photon-fusion monopole production in MadGraph is provided.
- Discussion on experimental implications of photon-fusion monopole searches.

## Abstract

The existence of magnetic monopoles, also predicted in some GUT theories, would symmetrise Maxwell equations and explain the charge quantisation. Searches for them are being performed in cosmic telescopes as well as in collider experiments, such as MoEDAL and ATLAS. In this report, we focus on the, least explored, photon-fusion mechanism, yet Drell-Yan results are discussed, too. Cross sections for monopoles of spin 0, 1/2 and 1 for an effective monopole-velocity-dependent magnetic charge are presented. For spin-1/2 and spin-1 monopoles, a magnetic-moment term is included, which is treated as a new phenomenological parameter and, together with the velocity-dependent coupling, allows for a perturbative treatment of the cross-section calculation. We present an appropriate implementation of photon-fusion and Drell-Yan processes into MadGraph UFO models, aimed to serve as a useful tool in monopole searches at LHC, especially for photon fusion, given that it has not been considered by experimental collaborations recently. Moreover, the experimental implications of such perturbatively reliable monopole searches are discussed.