Muon Pair Production in ep Collisions at HERA

TL;DR

This paper reports measurements of muon pair production in ep collisions at HERA, confirming Standard Model predictions and exploring additional leptonic events with high transverse momentum muons.

Contribution

First measurement of muon pair production cross sections at high di-muon masses in ep collisions at HERA, with detailed comparison to Standard Model predictions.

Findings

Measured cross sections agree with Standard Model.

No excess of events with additional high transverse momentum leptons.

Results validate photon-photon interactions as the dominant process.

Abstract

Cross sections for the production of two isolated muons up to high di-muon masses are measured in ep collisions at HERA with the H1 detector in a data sample corresponding to an integrated luminosity of 71 pb^-1 at a centre of mass energy of sqrt{s} = 319 GeV. The results are in good agreement with Standard Model predictions, the dominant process being photon-photon interactions. Additional muons or electrons are searched for in events with two high transverse momentum muons using the full data sample corresponding to 114 pb^-1, where data at sqrt{s} = 301 GeV and sqrt{s} = 319 GeV are combined. Both the di-lepton sample and the tri-lepton sample agree well with the predictions.