Hostname: page-component-8448b6f56d-gtxcr Total loading time: 0 Render date: 2024-04-24T01:22:53.515Z Has data issue: false hasContentIssue false
  • English
  • Français

The influence of a thermal plasma on synchrotron radiation†

Published online by Cambridge University Press:  09 March 2009

A. Crusius
A. Crusius
Affiliation:
Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-5300 Bonn 1, F.R.G.
Get access Rights & Permissions [Opens in a new window]

Abstract

The synchrotron emission from relativistic electrons in a thermal plasma with large-scale random magnetic fields is considered. In this case, the spectral synchrotron power of a single electron can be given in closed form allowing exact analytical expressions for the synchrotron emissivity, absorption coefficient, intensity and total energy loss of particles to be derived. The influence of various physical parameters such as gas density, magnetic field strength, particle's Lorentz factor on the resulting emissivities, intensities and energy loss is discussed in detail. Below the Razin– Tsytovich frequency vR = 20 Hz (ne/l cm−3) (B/l Gauss)−1, the spectral appearance of synchrotron radiation both in the optically thin and thick case is quite different than the vacuum behaviour. Since in the quasar broad line regions, vR is of the order 1011 Hz the suppression of synchrotron radiation may explain why most quasars are radio quiet. Likewise, the necessary physical conditions for the occurrence of synchrotron masering in the optically thick case are given. We obtain optical depth |τ|>1 for compact nonthermal sources. The total energy loss of a single particle is shown to be exponentially reduced at Lorentz factors less than γR = 2·1. 10−3 (ne/1 cm−3)½ (B/1 Gauss)−1.

Type
Research Article
Information
Laser and Particle Beams , Volume 6 , Issue 3 , August 1988 , pp. 421 - 436
Copyright
Copyright © Cambridge University Press 1988

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Abramowitz, M. & Stegun, I. A. 1970 Handbook of Mathematical Functions, National Bureau of Standards (Washington).Google Scholar
Angel, J. R. P. & Stockman, H. S. 1980 Ann. Rev. Astron. Astrophys. 18, 321.CrossRefGoogle Scholar
Bekefi, G. 1966 Radiation Processes in Plasmas, Wiley (New York).Google Scholar
Blumenthal, G. R. & Gould, R. J. 1970 Rev. Mod. Phys. 42, 237.CrossRefGoogle Scholar
Buchholz, H. 1953 Die konfluente hypergeometrische Funktion, Springer-Verlag (Berlin).CrossRefGoogle Scholar
Burbidge, G. R., Jones, T. W. & O'Dell, S. L. 1974. Astrophys. J. 193, 43.CrossRefGoogle Scholar
Cawthorne, T. V. 1985 Mon. Not. Roy. Astron. Soc. 216, 795.CrossRefGoogle Scholar
Crusius, A. & Schlickeiser, R. 1986 Astron. Astrophys. 164, L16.Google Scholar
Erdélyi, A. et al. 1954 Tables of Integral Transformations, Vol. 1, McGraw-Hill Book Co., Inc. (New York).Google Scholar
Gradshteyn, I. S. & Ryzhik, I. M. 1965. Table of Integrals, Series, and Products, Academic Press (New York).Google Scholar
Jones, T. W., O'Dell, S. L. & Stein, W. A. 1974 Astrophys. J. 192, 261.CrossRefGoogle Scholar
Kellerman, K. I. & Pauliny-Toth, I. I. K. 1981 Ann. Rev. Astron. Astrophys. 19, 373.CrossRefGoogle Scholar
McCray, R. 1966. Science 154, 1320.CrossRefGoogle Scholar
Melrose, D. B. 1972 Astrophysics and Space Science 18, 267.CrossRefGoogle Scholar
Melrose, D. B. 1980 Plasma Astrophysics, Vol. 1, Gordon and Breach Science Publishers (New York).Google Scholar
Miley, G. 1980 Ann. Rev. Astron. Astrophys. 18, 165.CrossRefGoogle Scholar
Moffet, A. T. 1975 In Kuiper, G. P. and Middlehurst, B. M. (eds.), Stars and Stellar Systems, Chicago University Press, Vol. 9, p. 211.Google Scholar
Scheuer, P. A. G. 1965 In Robinson, I.Schild, A., Schucking, E. L. (eds.), Quasi-Stellar Sources and Gravitational Collapse, University of Chicago Press, p. 373.Google Scholar
Schlickeiser, R. 1984 Astron. Astrophys. 136, 227.Google Scholar
Ulrich, M. H. et al. 1980 Mon. Not. Roy. Astron. Soc. 192, 561.CrossRefGoogle Scholar
Yukon, S. P. 1968 Astrophys. Lett. 2, 181.Google Scholar
Zheleznyakov, V. V. 1966 Zh. Eksp. Teo. Fiz. 51, 570; Soviet Phys. JETP 24, 381.Google Scholar