Publication: ApJ; First HAO Author: Alfred de Wijn; Authors as listed in article: A.G. de Wijn, J. de la Cruz Rodríguez, G.B. Scharmer, G. Sliepen, and P. Sütterlin
Example spectro-polarimetric data of Active Region 12471 in the Fe I lines at 630.2 nm. The observation was recorded on 2019-05-10 around 09:10 UT. Top row: images of the Stokes parameter in the blue wing of the 630.25 nm line at −90 mÅ from line center. Spectra at the black, red, and blue crosses are shown in the bottom row. The locations of the spectral sampling are indicated by crosses.
In 2014 HAO built a polarimetric modulator for the CRISP instrument on the Swedish 1-m Solar Telescope in La Palma, using the principles of polychromatic modulation previously developed by HAO scientists. This paper discusses the processes by which the modulator was designed, built, and tested. The modulator was installed and had been in use since 2015. It is working at close to optimal efficiency and has produced considerable scientific output.