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The Optical Emission from Gamma-Ray Quasars

Published online by Cambridge University Press:  05 March 2013

M. T. Whiting
Affiliation:
Department of Astrophysics and Optics, School of Physics, University of New South Wales, Sydney NSW 2052, Australia. [email protected]
P. Majewski
Affiliation:
Astrophysics Group, School of Physics, University of Melbourne, Victoria 3010, Australia
R. L. Webster
Affiliation:
Astrophysics Group, School of Physics, University of Melbourne, Victoria 3010, Australia; [email protected]
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Abstract

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We present photometric observations of six radio-loud quasars that were detected by the COMPTEL gamma-ray telescope. The data encompass seven wavebands in the optical and near infrared. After correction for Galactic extinction, we find a wide range in optical slopes. Two sources are as blue as optically-selected quasars, and are likely to be dominated by the accretion disc emission, while three others show colours consistent with a red synchrotron component. We discuss the properties of the COMPTEL sample of quasars, as well as the implications our observations have for multiwavelength modelling of gamma-ray quasars.

Type
Research Article
Copyright
Copyright © Astronomical Society of Australia 2003

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