Cryogenic contact resistance and material conductivities in astronomic instrumentation: an experimental characterization.

Abstract Astronomic instrumentation requires working at cryogenic temperatures and a high stability. It is crucial to understand the properties of materials and contacts among components within the cryostat to be able to achieve the thermal goals in astronomical applications. To enhance instrument cold structure designs, there’s a growing need to perform accurate Finite Element Method (FEM) analyses. Consequently, we conducted an experimental investigation to understand the properties of materials which we frequently employ in astronomical instrumentation at “Instituto de Astrofí sica de Canarias” (IAC). The data will be used as an input to our FEM Models in order to minimize uncertainties. This paper presents an experimental study focused on cryogenic contact resistance and material conductivities vital for the advancement of astronomical instrumentation. The investigation is focused on the characterization of contact resistance and conductive properties at low temperatures, specifically for copper, stainless-steel and aluminium (for conduction), and nylon and PTFE (for insulation). Through in site experimentation, we explore the behaviour of materials under cryogenic conditions, providing valuable knowledge for optimizing the performance and reliability of astronomical devices and the way of designing contacts inside a cryostat.