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The Nature of Flat Spectrum Sources

Published online by Cambridge University Press:  25 May 2016

D.B. Melrose
D.B. Melrose*
Affiliation:
Research Centre for Theoretical Astrophysics School of Physics, University of Sydney NSW 2006 Australia

Abstract

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Nonthermal radio sources near the Galactic Center with flat or weakly inverted spectra (S((ω) ∝ ωα with α ≳ 0) are attributed to optically thin synchrotron emission from a hard electron energy spectrum, N(ε) ∝ ε–α with a = 1 – 2α ≲ 1, produced by Fermi acceleration or diffusive shock acceleration at multiple shocks combined with a synchrotron pile up. This basic mechanism is also plausible for flat-spectrum AGN.

Type
Radio Source Modelling and Emission Mechanisms
Information
Symposium - International Astronomical Union , Volume 175: Extragalactic Radio Sources , 1996 , pp. 423 - 426
Copyright
Copyright © Kluwer 1996 

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