SPEX X-ray and UV spectral modeling

SPEX is a project generating atomic data and spectral fitting tools for high-resolution X-ray and UV spectroscopy in astrophysics. It has been developed since the 1970s at SRON Netherlands Institute for Space Research. The main product is the SPEX spectral fitting package, an interactive command-line program for the computation of emergent spectra of optically thin plasmas such as stellar coronal loop structures, supernova remnants (also including transient ionization effects), photo-ionized plasmas, and optically thick plasmas. These model spectra can be fitted to measured X-ray spectra from various X-ray observatories, like XMM-Newton and Chandra. SPEX has been optimized for high-resolution X-ray spectroscopy, which makes it especially suitable for analyzing grating and micro-calorimeter spectra.