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Data processing pipeline for UCoMP
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Polarimeter epochs #194

Open StevenTomczyk opened 1 year ago

StevenTomczyk commented 1 year ago

Discussion: The UCoMP polarimeter is calibrated with a calibration retarder and polarizer, resulting in a demodulation matrix (Dmx) that converts modulated intensities into Stokes I,Q,U,V. The Dmx elements are a function of the temperature of the polarimeter. Fortunately, we have monitored the temperature of the polarimeter throughout the mission. This has allowed us to calibrate the temperature dependence of the demodulation matrices. Midway through the mission, Damon implemented temperature control of the polarimeter.

Issue: Recently, Ben noticed that the Dmx elements, when plotted against time, possibly show some periods where they are above or below a trend. Are these epochs in polarimeter response, or just temperature departures?

bberkeyU commented 11 months ago

Using what we are seeing about the T_LCVR? lagging the TU_LCVR? Temperatures by a significant margin on most days. We should compare the filter vs. unfiltered temps when the polarization modulation calculations were made. It is unclear if this will help us fix or change the demodulation matrix, but hopefully, it will help us understand what was changing.