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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. mwhiting@phys.unsw.edu.au
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; rwebster@physics.unimelb.edu.au
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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

References

Bersanelli, M., Bouchet, P., & Falomo, R. 1991, A&A, 252, 854 Google Scholar
Bessell, M. S., Castelli, F., & Plez, B. 1998, A&A, 333, 231 Google Scholar
Brinkmann, W., Yuan, W., & Siebert, J. 1997, A&A, 319, 413 Google Scholar
Bloom, S. D., & Marscher, A. P. 1996, ApJ, 461, 657 Google Scholar
Carter, B. S., & Meadows, V. S. 1995, MNRAS, 276, 734 CrossRefGoogle Scholar
Collmar, W. 2001, in High Energy Gamma-Ray Astronomy, AIP Proceedings Volume 558, ed. F. A. Aharonian & H.J. Völk (Melville, NY: American Institute of Physics), 656 Google Scholar
Drinkwater, M. J., et al. 1997, MNRAS, 284, 85 Google Scholar
Graham, J. A. 1982, PASP, 94, 244 Google Scholar
Hartman, R. C., et al. 1999, ApJS, 123, 79 Google Scholar
Hunter, S. D., et al. 1993, ApJ, 409, 134 Google Scholar
Impey, C. D., & Tapia, S. 1990, ApJ, 354, 124 Google Scholar
Kovalev, Y. Y., Nizhelsky, N. A., Kovalev, Yu. A., Berlin, A. B., Zhekanis, G. V., Mingaliev, M. G., & Bogdantsov, A. V. 1999, A&AS, 139, 545 Google Scholar
McGregor, P., et al. 1994, in Infrared Astronomy with Arrays: The Next Generation, ed. I.S. McLean (Dordrecht: Kluwer), 299 Google Scholar
Mukherjee, R., et al. 1999, ApJ, 527, 132 Google Scholar
Raiteri, C. M., Villata, M., Lanteri, L., Cavallone, M., & Sobrito, G. 1998, A&AS, 130, 495 Google Scholar
Schlegel, D. J., Finkbeiner, D. P., & Davis, M. 1998, ApJ, 500, 525 Google Scholar
Schönfelder, V., et al. 2000, A&AS, 143, 145 Google Scholar
Whiting, M. T., Webster, R. L., & Francis, P. J. 2001, MNRAS, 323, 718 Google Scholar
Wright, A., & Otrupcek, R. 1990, Parkes Catalogue (Australian Telescope National Facility) (PKSCAT90)Google Scholar
Zhang, Y. F., Marscher, A. P., Aller, H. D., Aller, M. F., Terasranta, H., & Valtaoja, E. 1994, ApJ, 432, 91 Google Scholar