Busa`, I.

Contact Email: ebu@na.astro.it
Institute: Hamburger Sternwarte
First Coauthor: V. Andretta
Institute: Osservatorio Astronomico di Capodimonte
Second Coauthor: M. T. Gomez
Institute: Osservatorio Astronomico di Capodimonte
Subject Area: Stellar Atmospheres, Circumstellar Material
Waveband: Infrared
Technique: Spectroscopy
Presentation: Poster Display
Title: A non-LTE analysis of the Ca II infrared triplet as a diagnostic tool in solar-type stars
Abstract: We performed NLTE calculations of the profiles of the Ca II InfraRed Triplet (IRT: $\lambda$=8498, 8542, 8662 Å) for a grid of photospheric models with T_eff=4200, 5200, 6200 K, Log(g) =4.0, 4.5, 5.0 and [A/H]=0.0, -1.0, -2.0, showing the sensitivity of the profiles to changes in stellar parameters and the effect of departures from LTE. Simultaneous multi-line fitting of the Ca II IRT, Na I D and K I resonance lines is presented for a sample of eight dwarf and subgiant of spectral type F, G and K, and of relatively low activity level. [4th author: L. Terranegra - Osservatorio Astronomico di Capodimonte]