Physics of nonthermal radio sources

NOV 01, 1963

A Conference on Physics of Nonthermal Radio Sources was held on December 3–4, 1962, at the NASA Goddard Institute for Space Studies in New York City. Organized by G. R. Burbidge (University of California, San Diego), L. Woltjer (Leiden), and A. G. W. Cameron (Goddard Institute), the purpose of the meeting was to review recent observational and theoretical results in this rapidly developing field. Radio‐frequency radiation characterized by a nonthermal spectral energy distribution has been detected from Jupiter and from active regions on the Sun; however, the meeting was restricted to discussion of objects located outside the solar system, the so‐called “discrete sources.” Over one thousand of these localized regions of celestial radio emission have now been studied at two or more frequencies.

DOI: 10.1063/1.3050602

S. P. Maran

The fundamental observational problem in radio‐astronomical investigations of discrete sources is the determination of the precise positions and spectra of these objects, as well as measurement of the brightness distributions of those sources large enough to be resolved by existing equipment. Recently, polarimeter measurements at a number of frequencies have provided data on the percentage of linear polarization and position angle of the electric vector for some of the more intense sources. This work, in turn, has made it possible to study the effects of Faraday rotation on the cosmic radio waves, leading to model‐dependent estimates of the electron density and magnetic field strength in interstellar and intergalactic space.

References

1. W. E. Howard and S. P. Maran, in preparation.
2. See, for example: J. S. Greenstein and T. A. Matthews, Nature 197, 1041 (1963).https://doi.org/NATUAS

More about the Authors

S. P. Maran. University of Michigan.