Comparison of experimental techniques for evaluating the correction factor of a rectangular waveguide microcalorimeter

We have evaluated the correction factor of a WR-15 (50 to 75 GHz) rectangular waveguide microcalorimeter with four different techniques. The four methods are in agreement. Our initial uncertainty analysis indicates that the technique with the lowest uncertainty is one that utilized two identical microcalorimeter core sections whose reference planes were connected to each other. This initial uncertainty is smaller than expected, which will require us to re-evaluate uncertainty contributions that were neglected.