The Most Luminous Dust-Obscured Black Holes at zvirgul2-3

We propose to obtain XMMNewton observations for a complete fluxlimited sampleof 7 of the most mid infrared luminous quasars (log(L6um) > 47.5) at the mainepoch of galaxy and blackhole growth at z 2 3. The main objective is to studythe Xray properties of a new population of hyperluminous, heavily reddenedquasars with typical extinctions of 0.5 < E(B V ) < 2.0 and which are thereforenot detectable in widefield optical surveys. These broadline Type 1 reddenedquasars have the expected properties high Eddington ratios and moderatecolumndensities characteristic of the radiative feedback phase. We willconstrain the hard Xray luminosity and neutral hydrogen column density andcompare them to optically selected, essentially unobscured quasars. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]