# Gemini spectra of 12 000 K white dwarf stars

@article{Kepler2006GeminiSO,
title={Gemini spectra of 12 000 K white dwarf stars},
author={S. O. Kepler and B{\'a}rbara Garcia Castanheira and A. F. M. Costa and Detlev Koester},
journal={Monthly Notices of the Royal Astronomical Society},
year={2006},
volume={372},
pages={1799-1803}
}
• Published 11 October 2006
• Physics, Geology
• Monthly Notices of the Royal Astronomical Society
We report signal-to-noise ratio (S/N) ≃ 100 optical spectra for four DA white dwarf stars acquired with the GMOS spectrograph of the 8-m Gemini north telescope. These stars have 18 < g < 19 and are around T eff ∼ 12 000 K, where the hydrogen lines are close to maximum. Our purpose is to test if the effective temperatures and surface gravities derived from the relatively low-S/N ((S/N) ≈ 21) optical spectra acquired by the Sloan Digital Sky Survey through model atmosphere fitting are trustworthy…

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