Predicting Transport Effects of Scintillation Light Signals in Large-Scale Liquid Argon Detectors

TL;DR

This paper introduces a semi-analytical model for accurately and efficiently predicting scintillation light signals in large-scale liquid argon detectors, improving simulation speed and precision for neutrino and dark matter experiments.

Contribution

The authors develop a novel semi-analytical model that predicts scintillation light quantities and timing distributions with high precision, suitable for large-scale detectors like DUNE and SBND.

Findings

Achieves better than 10% precision in light prediction

Provides a method for timing distribution prediction

Models effects of wavelength-shifting, reflective layers

Abstract

Liquid argon is being employed as a detector medium in neutrino physics and Dark Matter searches. A recent push to expand the applications of scintillation light in Liquid Argon Time Projection Chamber neutrino detectors has necessitated the development of advanced methods of simulating this light. The presently available methods tend to be prohibitively slow or imprecise due to the combination of detector size and the amount of energy deposited by neutrino beam interactions. In this work we present a semi-analytical model to predict the quantity of argon scintillation light observed by a light detector with a precision better than $10\%$, based only on the relative positions between the scintillation and light detector. We also provide a method to predict the distribution of arrival times of these photons accounting for propagation effects. Additionally, we present an equivalent model to predict the number of photons and their arrival times in the case of a wavelength-shifting, highly-reflective layer being present on the detector cathode. Our proposed method can be used to simulate light propagation in large-scale liquid argon detectors such as DUNE or SBND, and could also be applied to other detector mediums such as liquid xenon or xenon-doped liquid argon.