Super soft X-ray source

A super soft X-ray source (SSS) is a type of astronomical object that emits X-rays in the "soft" X-ray range, typically between 0.1 and about 2 keV. These sources are characterized by their relatively low temperatures compared to other X-ray sources, which means that their emissions are primarily from lower-energy photons. Super soft X-ray sources are often linked to certain types of binary systems, particularly those involving white dwarfs.