Cryovacuum setup for optical studies of astrophysical ice

Sci Rep. 2023 Nov 30;13(1):21155. doi: 10.1038/s41598-023-48541-3.

Abstract

This paper presents a cryovacuum setup for the study of substances under near-space conditions. The setup makes it possible to study the infrared spectra, refractive index, and density of substances that are condensed from the vapor phase onto a cooled substrate in the temperature range from 11 to 300 K. At the same time, it is possible to obtain the ultimate pressure of 1 × 10-10 Torr in the vacuum chamber. The presented setup is based on FTIR spectroscopy (the spectral measurement range is 400-7800 cm-1) and laser interference, through which the important physical and optical parameters are determined. A number of experiments allow us to point out that the data obtained using this setup correlate well with the experiments of other authors. Due to the non-directional deposition of substances from the vapor phase, the ice formed resembles the one formed under cosmic conditions as closely as possible, which makes the presented setup particularly valuable. The presented cryovacuum setup can be used for the interpretation of data obtained during astrophysical observations, providing a means to determine the properties of cosmic objects.