Precision calculation of processes used for luminosity measurement at the ZEUS experiment

TL;DR

This paper provides a detailed calculation of the pe -> pe+gamma process with one-loop QED corrections, crucial for precise luminosity measurement at HERA, considering detection scenarios and background contributions.

Contribution

It introduces a comprehensive calculation including radiative corrections and analyzes detection scenarios for luminosity measurement at ZEUS.

Findings

Calculated photon and electron spectra with radiative corrections.

Analyzed detection scenarios with and without gamma-e coincidence.

Estimated background contributions from pe -> pel+l- process.

Abstract

The process pe -> pe+gamma with the photon emitted along the electron beam axis is used for luminosity measurement at HERA. In this paper the process is calculated including one-loop QED radiative corrections. In the ZEUS experiment, both the electron and the photon can be detected. Therefore both photon and electron spectra with and without the gamma-e coincidence are analyzed. We also calculate the process pe -> pel+l- which contributes to the background in the electron tagger.