Both accurate and precise gf-values for FeII lines

Abstract

We present a new set of oscillator strengths for 142 FeII lines in the wavelength range 4000-8000 A. Our gf-values are both accurate and precise, because each multiplet was globally normalized using laboratory data (accuracy), while the relative gf-values of individual lines within a given multiplet were obtained from theoretical calculations (precision). Our line list was tested with the Sun and high-resolution (R ~ 10^5), high-S/N (~700-900) Keck+HIRES spectra of the metal-poor stars HD 148816 and HD 140283, for which line-to-line scatter (sigma) in the iron abundances from FeII lines as low as 0.03, 0.04, and 0.05 dex are found, respectively. For these three stars the standard error in the mean iron abundance from FeII lines is negligible (sigma_mean <= 0.01 dex). The mean solar iron abundance obtained using our gf-values and different model atmospheres is A_Fe = 7.45 (sigma = 0.02).

Updated to conform to the published version. Typo (kindly informed by C. R. Cowley) in the wavelength of one FeII line (4278.159 instead of 4278.759) has been corrected

References in corpus (3)

• A grid of MARCS model atmospheres for late-type stars I. Methods and general properties
• Spectroscopic parameters for 451 stars in the HARPS GTO planet search program. Stellar [Fe/H] and the frequency of exo-Neptunes
• Metallicities for 13 nearby open clusters from high-resolution spectroscopy of dwarf and giant stars. Stellar metallicity, stellar mass, and giant planets