The Front-End electronics for the liquid Argon instrumentation of the LEGEND-200 experiment

TL;DR

This paper details the design, implementation, and commissioning of the front-end electronics for liquid Argon detection in the LEGEND-200 experiment, achieving low noise levels for rare neutrinoless double beta decay searches.

Contribution

It introduces a novel front-end electronics system optimized for low noise and high single-photon resolution in a radio-pure environment for the LEGEND-200 experiment.

Findings

Achieved a low electrical noise level of 250 μV peak-to-peak.

Successfully installed and commissioned the electronics system in July 2021.

Demonstrated stable operation in the experimental environment.

Abstract

In this paper we provide a detailed technical description of the Front-End (FE) electronics for the liquid Argon instrumentation of the LEGEND-200 experiment, searching for the very rare, hypothetical neutrinoless double $\beta$ decay process at the Italian Laboratori Nazionali del Gran Sasso. The design stems from the need to read out the silicon photo-multiplier response to the scintillation light in the liquid Argon with excellent single-photon resolution. The FE electronics is required to be placed far from the detectors to meet the experiment's radio-purity constraints. This constraint represents a challenge for a high signal-to-noise ratio. We address how this could be achieved in a stable way. The system was installed in July 2021 and has been commissioned with the rest of LEGEND-200, proving we could attain a very low overall level of electrical noise of 250 $\mu$V peak-to-peak.