Vol. 625
In section 14. Catalogs and data

CIELO-RGS: a catalog of soft X-ray ionized emission lines

Optical astronomy has been completely revolutionized by the passage from photometry to spectroscopy. In the X-ray band we are close to this revolution, which will become possible with the next generation of X-ray facilities. Grating instruments now allow for a taste of this revolution at low energies (0.5-2 keV). In this paper Mao et al. calculate a catalog of emission lines collected in ~2400 high-quality observations with the Reflection Grating Spectrometer on XMM-Newton. The outcome is a catalog of ~12,000 emission lines that are observed in a variety of astrophysical sources ranging from stars, X-ray binaries, and supernovae remnants, to active galactic nuclei and groups and clusters of galaxies. The idea of such a catalog as a research tool and a resource for the profession is almost invaluable.