A critical compilation of oscillator strengths for Fe II lines.

Abstract

We have compiled oscillator strengths for 848 Fe II lines of astrophysical interest. The Oscillator strengths from various sources like laboratory measurements, semi-empirical estimates and those derived using solar Fe II lines are critically examined for random and systematic errors. The errors of recent experimental determinations and also those of solar gf values are found to be lower compared to those of semi-empirical estimates. After omitting the measurements with large errors (i.e., more than 25% error) we have brought the oscillator strengths from the experimental and solar data to one scale by applying necessary corrections. Next, we have examined the semi-empirical gf values of Kurucz (1990a) which are overwhelmingly extensive and the gf values of Faweett (1987, 1988) by comparing them with experimental values.