Hyperluminous Quasars at z=2-3 Caught in the Radiative Feedback Phase

We have recently used XMMNewton observations to directly detect a powerfulquasar in a heavily dustshrouded galaxy at z2.5. This dusty quasar:ULASJ1234+0907, is observed in the AGN blowout phase and is among the mostluminous Xray quasars known (LXvirgul1E45 erg/s). Following these observations, wehave now spectroscopically confirmed two new extremely red, dusty broadlinequasars at zvirgul2.5 with similarly extreme properties to ULASJ1234+0907. We proposeto obtain Xray spectra of these in order to investigate the physical propertiesof the absorbing material and test models of radiative feedback on dust duringthe main epoch of galaxy formation and accretion activity in the Universe. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]