Calibration and simulation of ionization signal and electronics noise in the ICARUS liquid argon time projection chamber

TL;DR

This paper describes the calibration and simulation tuning of the ICARUS liquid argon TPC, improving charge response uniformity and matching simulation to data for enhanced neutrino detection accuracy.

Contribution

It introduces a data-driven equalization and simulation tuning method for the ICARUS TPC, reducing response non-uniformities and aligning Monte Carlo with real data.

Findings

Effective equalization removes spatial and temporal response non-uniformities.

Simulation tuning achieves good agreement with measured ionization signals.

Minimal residual bias between data and simulation after calibration.

Abstract

The ICARUS liquid argon time projection chamber (LArTPC) neutrino detector has been taking physics data since 2022 as part of the Short-Baseline Neutrino (SBN) Program. This paper details the equalization of the response to charge in the ICARUS time projection chamber (TPC), as well as data-driven tuning of the simulation of ionization charge signals and electronics noise. The equalization procedure removes non-uniformities in the ICARUS TPC response to charge in space and time. This work leverages the copious number of cosmic ray muons available to ICARUS at the surface. The ionization signal shape simulation applies a novel procedure that tunes the simulation to match what is measured in data. The end result of the equalization procedure and simulation tuning allows for a comparison of charge measurements in ICARUS between Monte Carlo simulation and data, showing good performance with minimal residual bias between the two.