Measurement of the thermal accommodation coefficient of helium on a crystalline silicon surface at low-temperatures

Autor:	Franke, Alexander, Sültmann, Nils, Reinhardt, Christoph, Croatto, Sandy, Schaffran, Jörn, Masalehdan, Hossein, Lindner, Axel, Schnabel, Roman
Rok vydání:	2024
Předmět:	Physics - Instrumentation and Detectors
Druh dokumentu:	Working Paper
Popis:	Next-generation gravitational wave observatories are expected to use cryogenically cooled, pendulum-suspended 200 kg test mass mirrors from a crystalline material such as crystalline silicon. During operation of the observatories, these mirrors undergo heating due to the absorption of laser radiation of up to a watt. Low noise cooling techniques need to be developed. Low-pressure helium exchange gas at 5 K might contribute to the challenging task. Here, we report the measurement of the helium accommodation coefficient $\alpha(11\,\mathrm{K} 0.7$ for temperatures < 20 K, which increases the cooling power compared to recently used assumptions. The idea of free molecular flow helium gas cooling is thus supported and might find application in some observatory concepts. Comment: 12 pages, 5 figures
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/2402.11977 Zobrazit plný text záznamu View this record from Arxiv