An improved method for measuring muon energy using the truncated mean of dE/dx

TL;DR

This paper introduces an improved muon energy measurement method using a truncated mean of dE/dx, significantly enhancing energy resolution in large Cherenkov detectors like IceCube.

Contribution

The paper presents a novel truncated mean technique for muon energy estimation, reducing the energy resolution spread compared to traditional methods.

Findings

Achieved a 26% improvement in energy resolution

Applicable to various large water, ice, and scintillator detectors

Method reduces the impact of high dE/dx fluctuations

Abstract

The measurement of muon energy is critical for many analyses in large Cherenkov detectors, particularly those that involve separating extraterrestrial neutrinos from the atmospheric neutrino background. Muon energy has traditionally been determined by measuring the specific energy loss (dE/dx) along the muon's path and relating the dE/dx to the muon energy. Because high-energy muons (E_mu > 1 TeV) lose energy randomly, the spread in dE/dx values is quite large, leading to a typical energy resolution of 0.29 in log10(E_mu) for a muon observed over a 1 km path length in the IceCube detector. In this paper, we present an improved method that uses a truncated mean and other techniques to determine the muon energy. The muon track is divided into separate segments with individual dE/dx values. The elimination of segments with the highest dE/dx results in an overall dE/dx that is more closely correlated to the muon energy. This method results in an energy resolution of 0.22 in log10(E_mu), which gives a 26% improvement. This technique is applicable to any large water or ice detector and potentially to large scintillator or liquid argon detectors.