Separating Faraday Rotation from an Achromatic Rotation: Frequency Leverage Across the Microwave Bands

This paper examines how cleanly a frequency-independent rotation can be separated from Faraday rotation in a magnetised plasma, using the very different frequency behaviour of the two effects across the bands where the microwave background is observed. The calculation is performed from stated assumptions and published polarisation measurements, using the deposited script so that every quoted number can be reproduced. The headline outputs are: faraday 30GHz deg = 0.11; faraday 150GHz deg = 0.0046; ratio 30 to 150 = 25; birefringence deg = 0.30. The treatment separates what the published measurements supply from what a theoretical framework must additionally provide; where a required quantity is not supplied, that absence is reported plainly as a negative result rather than replaced by an assumed value. The study is computed from stated assumptions and published inputs; it is not a new measurement. SIMULATED, NOT MEASURED in the sense that all derived quantities are calculated, not observed.