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arXiv · 1202.2236

The discovery of high power - high synchrotron peak blazars

P. Padovani·P. Giommi·A. Rau
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Abstract

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.

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P. Padovani, P. Giommi, A. Rau. 2012-02-10. The discovery of high power - high synchrotron peak blazars. https://doi.org/10.1111/j.1745-3933.2012.01234.x

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