The thermal structure of solar coronal loops and implications for physical models of coronae

Abstract

view Abstract Citations (43) References (40) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The thermal structure of solar coronal loops and implications for physical models of coronae Raymond, J. C. ; Foukal, P. Abstract EUV spectra of three active region loops observed above the solar limb with the SO55 spectrometer on Skylab are analyzed. It is noted that the lengths, peak temperatures, and pressures of the loops are typical of the X-ray coronal loops to which static models have been applied. It is found that the physical parameters of the coronal loop plasma derived from EUV spectra and raster pictures are not well represented by the static models. Although the loops also contain a significant quantity of cool plasma, no physical reason is found to differentiate them from other active region loops of similar length, pressure, and temperature. Several line ratios in the loop spectrum suggest departures from ionization equilibrium caused by rapid cooling. The source of this cooling material is discussed with reference to several models of loop dynamics. Publication: The Astrophysical Journal Pub Date: February 1982 DOI: 10.1086/159638 Bibcode: 1982ApJ...253..323R Keywords: Coronal Loops; Extreme Ultraviolet Radiation; Solar Corona; Solar Spectra; Stellar Models; Ultraviolet Spectra; Magnetohydrodynamics; Plasma Temperature; Skylab Program; Solar Limb; Solar Wind; Stellar Temperature; Solar Physics full text sources ADS |