Canonical high power blazars - Astrophysics > Cosmology and Nongalactic AstrophysicsReport as inadecuate

Canonical high power blazars - Astrophysics > Cosmology and Nongalactic Astrophysics - Download this document for free, or read online. Document in PDF available to download.

Abstract: The jets of powerful blazars propagate within regions relatively dense ofradiation produced externally to the jet. This radiation is a key ingredient tounderstand the origin of the high energy emission of blazars, from the X-ray tothe gamma-ray energy band. These external radiation fields control the amountof the inverse Compton radiation with respect to the synchrotron flux.Therefore the predicted spectral energy distribution SED will depend on wherethe jet dissipates part of its energy to produce the observed radiation. Weinvestigate in detail how the SED changes as a function of the location of thejet dissipation region, by assuming rather -standard- i.e. -canonical-prescriptions for the accretion disk and its X-ray corona, the profile of thejet magnetic field and the external radiation. The magnetic energy density of a-canonical- jet almost never dominates the radiative cooling of the emittingelectrons, and consequently the inverse Compton flux almost always dominatesthe bolometric output. This is more so for large black hole masses. Dissipationtaking place beyond the broad line region is particularly interesting, since itaccounts in a simple way for the largest inverse Compton to synchrotron fluxratios accompanied by an extremely hard X-ray spectrum. Furthermore it makesthe high power blazars at high redshift useful tools to study the optical to UVcosmic backgrounds.

Author: G. Ghisellini, F. Tavecchio Osserv. Astr. di Brera, Italy



Related documents