Resonance and Satellite Lines of Highly Ionized Iron in the Solar Spectrum Near 1.9 Å

A prominent emission feature frequently observed in the solar X-ray spectrum near 1.9 A at times of chromospheric flares is found, from data obtained by the Fifth Orbiting Solar Observatory, to consist of at least six spectral lines. In addition to the , , and possibly the 1'S0-23S1 transitions of Fe xxv, there appear to be satellite lines originating in highly excited Fe xxiv, Fe XXIII, and lower stages of ionization.