2011/09/20 by I. Ramirez, I. Ramírez, C. Allende Prieto +1 · 4 citations
Physics and Astronomy · #Astro and Planetary Science #Astrophysics and Star Formation Studies #Stellar, planetary, and galactic studies #astro-ph.SR
paper · pdf · doi:10.1088/0004-637x/743/2/135
ApJ, in press
arxiv created 2011/09/20 · openalex publication_date 2011/11/30 · arxiv updated 2015/05/29 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
We derive a self-consistent set of atmospheric parameters and abundances of 17 elements for the red giant star Arcturus: Teff = 4286+/-30 K, logg = 1.66+/-0.05, and [Fe/H] = -0.52+/-0.04. The effective temperature was determined using model atmosphere fits to the observed spectral energy distribution from the blue to the mid-infrared (0.44 to 10 um). The surface gravity was calculated using the trigonometric parallax of the star and stellar evolution models. A differential abundance analysis relative to the solar spectrum allowed us to derive iron abundances from equivalent width measurements of 37 FeI and 9 FeII lines, unblended in the spectra of both Arcturus and the Sun; the [Fe/H] value adopted is derived from FeI lines. We also determine the mass, radius, and age of Arcturus: M = 1.08+/-0.06 Msun, R = 25.4+/-0.2 Rsun, and t = 7.1(+1.5/-1.2) Gyr. Finally, abundances of the following elements are measured from an equivalent width analysis of atomic features: C, O, Na, Mg, Al, Si, K, Ca, Sc, Ti, V, Cr, Mn, Co, Ni, and Zn. We find the chemical composition of Arcturus typical of that of a local thick-disk star, consistent with its kinematics.