Desaturating SDO/AIA Observations of Solar Flaring Storms

Image saturation has been an issue for several instruments in solar astronomy, mainly at EUV wavelengths. However, with the launch of the Atmospheric Imaging Assembly (AIA) as part of the payload of the Solar Dynamic Observatory image saturation has become a big data issue, involving around 105 frames of the impressive data set the telescope has been providing every year since 2010 February. This paper introduces a novel desaturation method that utilizes a sparsity constraint to solve the inverse scattering problem of determining the signal in the primary saturation region from the knowledge of the diffraction fringes produced by the instrument point-spread function. The method works without any need of a priori information on the image background and therefore can be applied even for desaturation of several consecutively deteriorated frames recorded during long-lasting intense solar storms. This peculiar methodological property could make this algorithm a possible tool for the realization of an automatic pipeline for the processing of the whole AIA data archive.