Abstract
Variation of electron energy and angular distributions has been studied as a function of column density by combining small-angle analytical treatment with large-angle Monte Carlo calculations. The distributions have been calculated for initial electron energy 300 keV and various incidence directions. Using these distributions and Sauter bremsstrahlung cross-section differential in photon energy and emission angle, we have calculated the X-ray energy and angular distributions for photon energies 10, 20, 50, 100, 150 and 200 keV. By taking the ratio of X-ray flux at 90 and 180°, we have computed the anisotropy ratio A as function of column density. Calculated anisotropy ratio compares well with ISEE-3 and PVO observations.
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Koul, P.K., Rausaria, R.R. & Khosa, P.N. Calculation of anisotropy ratio of hard X-rays from solar flares — evidence for continuous electron injections/accelerations. Sol Phys 108, 139–150 (1987). https://doi.org/10.1007/BF00152083
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DOI: https://doi.org/10.1007/BF00152083