A zero point and accidental errors for published values of [Fe/H] for cool giants

Department of Physics and Astronomy, N283 ESC, Brigham Young University, Provo, UT 84602-4360, U.S.A.

Received: 24 July 1998
Accepted: 23 September 1998

Abstract

This paper is one of a series based on published values of [Fe/H] for late-type evolved stars. Only values of [Fe/H] from high-dispersion spectroscopy or related techniques are used. The narrative in this paper begins at a point where mean values of [Fe/H] have been derived for ϵ Vir, α Boo, β Gem, and the Hyades giants. By using these stars as standard stars when necessary, a zero-point data base is assembled. This data base is then expanded into its final version by correcting and adding additional data in a step-by-step process. As that process proceeds, data comparisons are used to establish rms errors. Derived rms errors per datum are found to be about 0.10-0.12 dex, and they appear to be too large to be explained by line-to-line scatter and temperature effects.