The low-frequency compact source in the Crab nebula.
Abstract
The parameters of the low-frequency compact source in the Crab nebula are given. In the decameter-wavelength range its coordinates, α(1950.0) = 5h31m31s, 62±0s.22 and δ(1950.0) = 21°58arcmin52arcsec, 8±3arcsec.9, coincide within the error limits with those of the pulsar PSR 0531+21. The apparent angular size of the compact source varies with the frequency ν as θ0 ∝ ν-1.95±0.25 from 3arcsec.3 at 12.6 MHz to 0arcsec.18 at 75 MHz. The flux density of the integral radio emission of the compact source and the pulsar Sν(Jy) in function of the frequency ν(Hz) is approximated by the expression Sν = 44(1+2y2)-1y-5/3 where y = ν/(1.6×108). The spectrum of the summary emission of the compact source and the pulsar is explained by coherent curvature radiation of charged clots with effective thickness 60 cm.
- Publication:
-
Astronomicheskii Zhurnal
- Pub Date:
- August 1987
- Bibcode:
- 1987AZh....64..734B
- Keywords:
-
- Crab Nebula;
- Decametric Waves;
- Low Frequencies;
- Pulsars;
- Radiant Flux Density;
- Radio Spectra;
- Emission Spectra;
- Spectrum Analysis;
- Stellar Spectra;
- Stellar Spectrophotometry;
- Astrophysics