X-Ray Selected Type 2 QSOs and Their Host Galaxies

We present a large sample of X-ray selected type 2 QSOs from the XMM-COSMOS survey. Type 2 QSOs are luminous AGN whose central engines are obscured by large amounts of gas and dust. The selection criteria we have used are based on high X-ray luminosity (L_X > 10⁴⁴ erg s^-1) and heavy obscuration (N_H > 10²² cm^-2). We derived stellar masses and star-formation rate estimates for the host galaxies from the best fit of the observed photometry. Type 2 QSOs are generally hosted in massive galaxies with on-going star formation.