Comparison of measurement methods for the correction factor of microcalorimeters

Abstract

Correction factor is one of the key parameters in the characterization of a microcalorimeter. The correction factor of the microcalorimeter removes the power loss contribution to the RF power measurement in the calibration of an RF power sensor. National Metrology Institutes choose the measurement method of the microcalorimeter correction factor based on its advantages and disadvantages. Here, the determination of the correction factor using three methods, i.e. offset short, short foil, and VNA method has been conducted for an R 500 waveguide microcalorimeter. The results are compared, and the correction factors of all methods show a good agreement. Also analysed are the measurement uncertainties of the three techniques. The measurement uncertainty of the correction factor is the most significant uncertainty source for the determination of effective efficiency of a transfer standard.