A Grid of Synthetic Spectra for Subdwarfs: Non-LTE Line-blanketed Atmosphere Models

Abstract

A new grid of detailed atmosphere model spectra for hot and moderately cool subdwarf stars is presented. High-resolution spectra and synthetic photometry are calculated in the range from 1000-10,000 angstrom using non-LTE fully line-blanketed atmosphere structures. Our grid covers eight temperatures within 10,000 <= T (eff) [K] <= 65,000, three surface gravities in the range 4.5 <= log g [cgs] <= 6.5, two helium abundances matching two extreme helium-rich and helium-poor scenarios, and two limiting metallicity boundaries regarding both solar ([Fe/H] = 0) and Galactic halos ([Fe/H] = -1.5 and [alpha/Fe] = +0.4). Besides its application in the determination of fundamental parameters of subdwarfs in isolation and in binaries, the resulting database is also of interest for population synthesis procedures in a wide variety of stellar systems.