Millikelvin-precision temperature sensing for advanced cryogenic detectors

TL;DR

This paper introduces a novel cross-calibration technique for resistance temperature detectors in cryogenic liquids, achieving millikelvin precision crucial for cryostat and detector performance in large-scale experiments.

Contribution

The paper presents a new calibration method for RTDs in cryogenic liquids, enabling temperature measurements with 2.5 mK precision for cryogenic detector systems.

Findings

Achieved temperature measurement precision of 2.5 mK.

Validated and optimized temperature monitoring system for DUNE prototype.

Enhanced understanding of cryogenic temperature calibration techniques.

Abstract

Precise temperature monitoring -- to the level of a few milli-Kelvin -- is essential for the operation of large-scale cryostats requiring a recirculation system. In particular, the performance of Liquid Argon Time Projection Chambers -- such as those planned for the DUNE experiment -- strongly relies on proper argon purification and mixing, which can be characterized by a sufficiently dense grid of high-precision temperature probes. In this article, we present a novel technique for the cross-calibration of Resistance Temperature Detectors in cryogenic liquids, developed as part of the temperature monitoring system for a DUNE prototype. This calibration has enabled the validation and optimization of the system's components, achieving an unprecedented precision of 2.5 mK.