%0 Journal Article %T The discovery of high power - high synchrotron peak blazars %A P. Padovani %A P. Giommi %A A. Rau %J Physics %D 2012 %I arXiv %R 10.1111/j.1745-3933.2012.01234.x %X We study the quasi-simultaneous near-IR, optical, UV, and X-ray photometry of eleven gamma-ray selected blazars for which redshift estimates larger than 1.2 have been recently provided. Four of these objects turn out to be high-power blazars with the peak of their synchrotron emission between ~ 3 x 10^15 and ~ 10^16 Hz, and therefore of a kind predicted to exist but never seen before. This discovery has important implications for our understanding of physical processes in blazars, including the so-called "blazar sequence", and might also help constraining the extragalactic background light through gamma-ray absorption since two sources are strongly detected even in the 10 - 100 GeV Fermi-LAT band. Based on our previous work and their high powers, these sources are very likely high-redshift flat-spectrum radio quasars with their emission lines swamped by the non-thermal continuum. %U http://arxiv.org/abs/1202.2236v1