The telescopes feed two identical but independent full Stokes IQUV polarimeters. The polarizing units are based on interference-suppressed super-achromatic retarder plates and Foster prisms. A total of four fibers will simultaneously direct two ordinary and two extraordinary light beams to the spectrograph. Both polarimetric units are layed out in a modular design, each one optimized to the polarization state in which it is used. A number of observing modes can be chosen that are optimized to the type of polarization that is expected from the target, e.g. circularly and linearly polarized light simultaneously, or linearly polarized light in both polarimeters, or integral light from one and polarized light from the other telescope, a.s.o.. Calibration would be provided for each polarimeter separately.

• Polarimeter commissioning took place in September 2017. Read more…

Polarimetric calibration @ L3 rd