The degree of anisotropy of cosmic ray electrons of solar origin

Allum, F. R. ; Palmeira, R. A. R. ; Rao, U. R. ; McCracken, K. G. ; Harries, J. R. ; Palmer, I. (1971) The degree of anisotropy of cosmic ray electrons of solar origin Solar Physics, 17 (1). pp. 241-268. ISSN 0038-0938

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Data obtained by the Explorer 34 satellite regarding the degree of anisotropy of ≳ 70 keV electrons of solar origin are reported. It is shown that the anisotropies are initially field aligned, and that they decay to ≲10% in a time of the order of 1 hr. The decays of the concurrent ionic and electronic anisotropies for one well observed event are in good agreement with the diffusive propagation model of Fisk and Axford. The data suggest parallel diffusion coefficients for both ions and electrons that are rigidity independent. From considerations of a long lived electron event, it is shown that the electronic fluxes exhibit 'equilibrium' anositropies at late times. These are interpreted as indicating that convective removal at the solar wind velocity is the dominant mechanism whereby solar cosmic ray electrons (≃ 70 keV) leave the solar system. They also indicate that there is a positive density gradient at late times in a solar electron event. The data suggest that this was established prior to the establishment of a similar gradient for the cosmic ray ions.

Item Type:Article
Source:Copyright of this article belongs to Springer.
ID Code:42743
Deposited On:06 Jun 2011 09:15
Last Modified:17 May 2016 23:56

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