Analysis of the extreme-ultraviolet quiet solar spectrum.

The solar EUV spectrum provides a suitable approach for the study of the solar atmosphere because the emission lines and continua are formed at temperatures ranging from about 10,000 K, representative of the low chromosphere, to temperatures in excess of 3 million degrees K, originating predominantly in active regions. The OSO-4 experiment obtained spectra originating from a region at the center of the quiet solar disk. The spectrum is used to derive the emission measures and the chemical abundances for a number of elements. A one-dimensional temperature and density model is constructed from this analysis.