New AE values for iron

Abstract

Astronomers are greatly interested in accurate determinations of the abundance of solar iron, determinations that are of critical importance in developing models of the solar atmosphere. They have been puzzled by determinations that seemed to give a much smaller iron abundance in the sun's photosphere than in the corona. The accuracy in determining such abundances is critically dependent upon a basic atomic characteristic—the atomic oscillator strengths, or ƒ values, of the element in question. Gross deviations between a few newly measured Fe I ƒ values in the literature and older, widely accepted comprehensive data tables led atomic physicists J.M. Bridges and W.L. Wiese of the National Bureau of Standards (U.S. Department of Commerce) Institute for Basic Standards to remeasure the ƒ values for iron on a comprehensive scale in hopes of resolving this discrepancy.