Linear Polarisation
- Make sure you have requested the half-wave plate in your NOT NIRF. Should
only be installed by staff.
- In the PP program you choose Linear Polarisation under MODE menu, which
is default by starting up PP. Also, the default set-up for linear
polarisation is 10s integration time and a cycle of 4 complete polarisation
measurements. Each measurement consists of 8 integrations. These are
simultaneous integrations in UBVRI of the ordinary and the extra-ordinary
component through the calcite prism as the half-wave retarder is rotated in
steps of
22.5 degrees. Such a measurement takes about 3.5 minutes with the default
parameters, which are normally used for stellar observations, and a complete
cycle of 4 measurements takes about 15 minutes, after which you should take a
sky integraton. See the Signal to Noise plot for
different magnitudes and number of cycles using this setup.
-
The highest time resolution in this mode is about 60 seconds (and about 5
seconds for the simultaneously obtained photometry).
