Momentum measurement by the Multiple Coulomb Scattering method in the OPERA lead emulsion target

TL;DR

This paper introduces a novel method for measuring charged particle momentum using Multiple Coulomb Scattering in OPERA's lead emulsion detector, validated through Monte Carlo simulations and test beam data.

Contribution

It presents a new algorithm for momentum measurement via MCS in nuclear emulsions, validated with Monte Carlo simulations and experimental data from OPERA.

Findings

The MCS-based momentum measurement agrees with electronic detector measurements within uncertainties.

The algorithm accurately describes test beam data and neutrino interaction events.

The method enhances momentum measurement precision in emulsion detectors.

Abstract

A new method of momentum measurement of charged particles through Multiple Coulomb Scattering (MCS) in the OPERA lead emulsion target is presented. It is based on precise measurements of track angular deviations performed thanks to the very high resolution of nuclear emulsions. The algorithm has been tested with Monte Carlo (MC) pions. The results are found to describe within the expected uncertainties the data obtained from test beams. We also report a comparison of muon momenta evaluated through MCS in the OPERA lead emulsion target with those determined by the electronic detectors for neutrino charged current interaction events. The two independent measurements agree within the experimental uncertainties, and the results validate the algorithm developed for the emulsion detector of OPERA.