Discovery of a Type 2 Quasar at [ITAL]z[/ITAL] = 0.9

We report the discovery of a narrow-line, X-ray-luminous galaxy at z = 0.9, which is the counterpart of an X-ray source detected in a deep pointing observation with the Advanced Satellite for Cosmology and Astrophysics . The object has a hard X-ray spectrum; it is significantly detected only in the 2-10 keV band, with a flux of ~1 × 10 -13 ergs s -1 cm -2 . Its rest X-ray luminosity in the 2-10 keV band is estimated to be ~1 × 10 44 ergs s -1 ( q 0 = 0.5, H 0 = 50 km s -1 Mpc -1 ). The optical spectrum shows high-excitation and high-ionization lines but no significant broad emission line component. All these properties imply that this object is a "type 2 QSO."