| Popis: |
The production of bremsstrahlung X-rays associated with energetic auroral electron streams is computed, and the ionization rate due to the X-rays is deduced. The incident electron stream is assumed to have an isotropic angular distribution over the downward hemisphere; energy distribution functions which closely predict luminosity profiles of N 2 + radiation are adopted. Bremsstrahlung ionization production peaks at altitudes between 40 and 74 km for electron streams yielding auroral height-luminosity profiles which have a maximum in the range 100 to 120 km, but the ionization rate due to bremsstrahlung is several powers of ten below that obtained from direct ionization by electron impact. The spectral distribution and flux of X-rays associated with auroral bombardment are predicted at various altitudes, particularly in the height range reached by balloons. |
