A general search for new phenomena in ep scattering at HERA

TL;DR

This paper conducts a comprehensive, model-independent search for deviations from the Standard Model in electron-proton collisions at HERA, analyzing all high transverse momentum event topologies in a single, systematic framework.

Contribution

It introduces a novel, all-encompassing analysis method for detecting deviations in ep scattering, covering all event topologies with a unified statistical approach.

Findings

Most event classes agree with the Standard Model

A significant deviation was observed in a topology with a muon, missing momentum, and a jet

The deviation aligns with a previously reported anomaly

Abstract

A model-independent search for deviations from the Standard Model prediction is performed in e^+ p and e^- p collisions at HERA using H1 data corresponding to an integrated luminosity of 117 pb^-1. For the first time all event topologies involving isolated electrons, photons, muons, neutrinos and jets with high transverse momenta are investigated in a single analysis. Events are assigned to exclusive classes according to their final state. A statistical algorithm is developed to search for deviations from the Standard Model in the distributions of the scalar sum of transverse momenta or invariant mass of final state particles and to quantify their significance. A good agreement with the Standard Model prediction is observed in most of the event classes. The most significant deviation is found for a topology containing an isolated muon, missing transverse momentum and a jet, consistent with a previously reported observation.