Image processing for the Sunrise Spectropolarimeter and Imager (SUSI)

SANCHEZ, M.; ZUCARELLI, G.; IGLESIAS, F. A; FELLER, A.; LAGG, ANDREAS; GANDORFER, ACHIM; RIETMULLER, TINO

Buenos Aires

Conferencia; 64va Reunión Anual de la AAA; 2022

Asociación Argentina de Astronomía

Sunrise is a 1-m optical solar observatory that can reach very high spatial resolution and magneticsensitivity while mounted in a stratospheric balloon. Its main science function is to study magnetic fields andplasma flows in the solar atmosphere. Its third flight is planned for July 2022 and will carry three full-Stokesspectropolarimeters that can simultaneously cover selected spectral lines from 310 to 860 nm. The Sunrise UVSpectropolarimeter and Imager (SUSI), operates in the 310 – 430 nm range, covering thousands of spectral linesthat are not easily reached from the ground and thus largely unexplored. In this study, we present the results ofthree processing techniques that are planned to be introduced into the data reduction routines of SUSI, namely a)The reduction of variable diffraction fringes, present in the spectropolarimometric images, using Fourier filtering,b) The reduction of hot or cold pixels using a median filter with optimized parameters, and c) The correction ofthe CMOS cameras non-linearities using calibration tables acquired in laboratory.