Polarimetry

We have taken some B and R measurements with the FAPOL polarization unit of the standards and candidate standards currently investigated with TurPol in order to find the internal calibration between these two instruments. We also took repeated zero-polarization standards at various rotator position and with many retarder angles. These data are currently being reduced by Tapio.

The `Wedged Double Wollaston' (WeDoWo) prism for one-shot polarimetric observations with ALFOSC has been tested. Reducing the data has been less straight forward than expected. However, it has been possible to obtain an accuracy with the device which similar to what is obtained from raw FAPOL data using four retarder plate positions.

Also some spectropolarimetry test data was taken with the WeDoWo, but this still needs to reduced and analyzed. Likely more tests will be needed before we can commission this mode.