Abstract
Using measurements of EUV and X-ray spectral lines we derive the differential emission measure vs electron temperature T from the transition region to the corona of an active region (105 T <5 × 106 K). The total emission measure and radiative losses are of order 3 × 1048 cm−3 and 4 × 1026 ergss−1 respectively. The emission measure at T > 106 K (i.e. that mainly responsible for the X-ray emission) is about 75% of the total. We also examine the use of Mg x λ 625 Å as an indicator of coronal electron density. A set of theoretical energy balance models of coronal loops in which the loop divergence is a variable parameter is presented and compared with the observations. Particular attention is given to the limitations inherent in any such comparison.
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Levine, R.H., Pye, J.P. The coronal and transition region temperature structure of a solar active region. Sol Phys 66, 39–60 (1980). https://doi.org/10.1007/BF00150517
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DOI: https://doi.org/10.1007/BF00150517