SOLAR EMISSION-LINES REVISITED - EXTENDED STUDY OF MAGNESIUM

Edlens polarization formula is found to fit the high-l solar infrared emission lines attributed to Mg I to the accuracy of the high-precision obervations. For several previously unidentified weak lines, assignments are made, a few to Mg I. With some revision of laboratory energy levels, a more precise ionization limit for Mg I is determined to be 61,671. 056 (10)cm** minus **1. The fine structure of the two strongest lines at 811 and 818 cm** minus **1 is found to consist of 4 components spaced about 0. 001 cm** minus **1 apart with nearly equal intensities. Their behavior in the penumbra magnetic field is well described by the Paschen-Back effect. Their line profile, polarization, and directional properties are discussed.