Design and Performance of a Lead Fluoride Detector as a Luminosity Monitor

TL;DR

This paper details the design, calibration, and operation of lead fluoride Cherenkov calorimeters used for precise luminosity measurements in a particle physics experiment, including simulation methods and detector performance.

Contribution

It introduces a novel detector system for luminosity monitoring and provides comprehensive calibration and simulation procedures for accurate measurements.

Findings

Successful detection of scattering events with high precision

Effective calibration and simulation of detector response

Demonstrated reliable performance in the OLYMPUS experiment

Abstract

Precise luminosity measurements for the OLYMPUS two-photon exchange experiment at DESY were performed by counting scattering events with alternating beams of electrons and positrons incident on atomic electrons in a gaseous hydrogen target. Final products of M{\o}ller, Bhabha, and pair annihilation interactions were observed using a pair of lead fluoride Cherenkov calorimeters with custom housings and electronics, adapted from a system used by the A4 parity violation experiment at MAMI. This paper describes the design, calibration, and operation of these detectors. An explanation of the Monte Carlo methods used to simulate the physical processes involved both at the scattering vertices and in the detector apparatus is also included.