Radio Spectral Envelopes - Theoretical Multiple Adiabatic Bursts

Abstract

view Abstract Citations (1) References (25) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Radio Spectral Envelopes - Theoretical Multiple Adiabatic Bursts Mitchell, K. J. ; Usher, P. D. Abstract The distinction is drawn between the characteristic optical depth for the instantaneous continuum spectrum of an evolving radio source, and that for the light curve of the source. The latter is defined and evaluated for a single burst in the standard adiabatically expanding electron-synchrotron model. Under appropriate simplifying assumptions, a finite sequence of N such bursts is considered, and the characteristic equation for optical depths is derived, from which flux density extremes are calculated. The assumptions that all bursts have similar electron energy spectra, and that they are all separated by the same amount co in time, can together be regarded as a logical extension of the standard single-burst model. Various limiting cases are analyzed. The relation between the optical depth and the time eigenvalues is noted. Invariance of the shape of spectral envelopes to burst rate ω∼-1 is demonstrated. The limiting case of an infinite sequence of bursts is formulated in such a way as to facilitate computations. Various cases are evaluated numerically. The final section discusses the applicability of these results to a few selected problems. Publication: The Astronomical Journal Pub Date: April 1981 DOI: 10.1086/112925 Bibcode: 1981AJ.....86..625M full text sources ADS |