Self-compensating Light Calorimetry with Liquid Argon Time Projection Chamber for GeV Neutrino Physics

TL;DR

This paper demonstrates that Liquid Argon TPCs can self-compensate for missing hadronic energy through recombination luminescence, enabling effective light calorimetry for GeV neutrino energy reconstruction with comparable resolution to charge calorimetry.

Contribution

It introduces the concept of self-compensating light calorimetry in LArTPCs, showing its potential for improved neutrino energy measurement across a broad energy range.

Findings

Good e/h response ratio (1-1.05) achieved across various electric fields.

Light calorimetry can match charge calorimetry energy resolution under ideal conditions.

Position-dependent correction mitigates nonuniform light collection issues.

Abstract

The Liquid Argon Time Projection Chamber (LArTPC) is a powerful dual calorimeter capable of estimating particle energy from both ionization charge and scintillation light. Our study shows that, due to the recombination luminescence, the LArTPC functions as a self-compensating light calorimeter: the missing energy in the hadronic component is compensated for by the increased luminescence relative to the electromagnetic component. Using 0.5--5 GeV electron neutrino charged current interactions as a case study, we show that good compensation of the electron-to-hadron response ratio (e/h) from 1--1.05 can be achieved across a broad range of drift electric fields (0.2--1.8 kV/cm), with better performance for neutrino energies above 2 GeV. This study highlights the potential of light calorimetry in LArTPCs for GeV neutrino energy reconstruction, complementing traditional charge calorimetry. Under ideal conditions of uniform light collection, we show that LArTPC light calorimetry can achieve an energy resolution comparable to the charge imaging calorimetry. Challenges arising from nonuniform light collection in large LArTPCs can be mitigated with a position-dependent light yield correction derived from 3D charge signal imaging.