X-ray spectral characterization of optically selected NL Seyfert 1 galaxies

We propose the observation with XMMNewton of a sample of 14 optically selectedNarrowLine Seyfert 1 galaxies (NLS1) discovered in the Sloan Digital Sky Survey(SDSS) and never observed in Xrays. The key aim of this project is the detailedcharacterization of the Xray spectral properties of optically selected NLS1.Moreover, since most NLS1 known to date are Xray selected, this study will alsoassess if their 0.510 keV spectral properties change with the selection method.