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arXiv · 2110.02229

A Grid of Synthetic Spectra for Subdwarfs: Non-LTE line-blanketed atmosphere models

Thayse A. Pacheco·Marcos P. Diaz·Ronaldo S. Levenhagen·Paula R. T. Coelho
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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{\AA} to 10,000{\AA} using Non-LTE fully line-blanketed atmosphere structures. Our grid covers eight temperatures within 10,000<Teff [K]<65,000, three surface gravities in the range 4.5<logg [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 halo ([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.

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Thayse A. Pacheco, Marcos P. Diaz, Ronaldo S. Levenhagen, Paula R. T. Coelho. 2021-10-05. A Grid of Synthetic Spectra for Subdwarfs: Non-LTE line-blanketed atmosphere models. https://doi.org/10.3847/1538-4365%2Fac2508

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