Abstract
Absolute intensities and wavelengths for 98 X-ray emission lines between 9 and 22.5 Å are reported. The active region spectra were obtained with three rocket-borne crystal spectrometers. Identifications are proposed for 62 of the lines and a model of the emitting plasma is constructed from the intensities of the strongest lines. The emission measure (N 2e V) of the model peaks at 3 × 106 K with a value of 1.5 × 1047 cm−3 and decreases to 1046 cm−3 at 5 × 106 K. Effective oscill and collision strengths are calculated for the other transitions that are observed. The relative intensities of O viii and Ne ix give an oxygen : neon abundance ratio of 8 ∶ 1. The intensities of the satellite lines to helium-like lines are investigated and it is shown that these lines can be used with confidence in constructing active region models.
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Work commenced during the tenure of a Science Research Council Research Fellowship in the Physics Department of Leicester University.
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Parkinson, J.H. The analysis of a high resolution X-ray spectrum of a solar active region. Sol Phys 42, 183–207 (1975). https://doi.org/10.1007/BF00153295
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DOI: https://doi.org/10.1007/BF00153295