Thermal Considerations on Adiabatic Coaxial Line for Microcalorimeter Measurements

This paper presents electric and thermal analysis of adiabatic coaxial line with two narrow plastic-filled gaps in the outer coaxial conductor, for the microcalorimeter power measurements over a UWB frequency range. The gaps serve to reduce the thermal transfer from the ambient into microcalorimeter and thereby to reduce measurement uncertainties in power measurements. The measurements on the manufactured line prototype are presented and shown to have a good correspondence with simulations.