1999/06/01 by R. E. M. Griffin, A. E. Lynas-Gray · 2 citations
Physics and Astronomy · Engineering · #Stellar, planetary, and galactic studies #Scientific Research and Discoveries #Astronomical Observations and Instrumentation
paper · pdf · doi:10.1086/300878
openalex publication_date 1999/06/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
We construct an empirical energy distribution for Arcturus from published scans, integrate it to obtain the total flux, and combine the latter with precise interferometric measurements of the limb-darkened angular diameter to derive the effective temperature. We conclude that the best value that can be derived within the framework of the associated assumptions is T eff = 4290 ± 30 K. We then select a grid of model-atmosphere energy distributions by Kurucz and extract T eff /log g /[Fe/H] by a least-squares fit to the adopted energy distribution. With the value of T eff already constrained, we could investigate values for the surface gravity and metallicity of Arcturus; our results are log g = 1.9, [Fe/H] = -0.68, and R = 23 R ⊙ . However, we discuss evidence that relevant grids of models may not contain sufficient opacity.