Determination of Solar Abundances by a Method of Spectrum Synthesis
Abstract
A procedure is described for obtaining the solar abundance, A, of an element, or more accurately gf A (where g is the statistical weight of the lower level and f is the oscillator strength). Instead of using the equivalent width of a line, one employs the entire profile. If the line falls in a crowded region of the spectrum where blending is severe, one attempts to reproduce the observed intensity distribution, I~(O,j~), over the relevant wavelength region by including all relevant boundbound transitions. The cal culation has been programmed for an IBM 360/75 computer. We assumed that when the parameters of the lines contributing to this region are adjusted so that the computed Ix(O,~~) distribution matches the observed Ix(O,~~) distribution, the correct values of the parameter gfA have been obtained. The method is useful for those elements which are represented only by lines falling in crowded regions of the solar spectrum. The adjustable parameters are gfA and the damping constant, I'. Depending on the basic physical data and the number of perturbing lines in the region, the value of gfA may be established to within 0.1 in the logarithm to the base 10. The damping constant, however, might be in error by a factor of 2
 Publication:

The Astrophysical Journal
 Pub Date:
 July 1968
 DOI:
 10.1086/149653
 Bibcode:
 1968ApJ...153..235R