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Analysis of DA White Dwarfs from the McCook & Sion Catalog

A. Gianninas·P. Bergeron·P. Dufour
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Abstract

The Sloan Digital Sky Survey has already doubled the number of spectroscopically identified white dwarfs. However, there remains a wealth of white dwarfs in the McCook & Sion catalog for which little or nothing is known. We have thus undertaken a spectroscopic survey of all Northern hemisphere DA white dwarfs from this catalog in order to (1) confirm the spectroscopic classification, and (2) provide measurements of Teff and log g for each star. As part of this project, we have also secured spectroscopic data for all DA stars with high-speed photometric measurements available, in order to study the purity of the ZZ Ceti instability strip, which has recently been challenged, once again.

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A. Gianninas, P. Bergeron, P. Dufour. 2005-03-04. Analysis of DA White Dwarfs from the McCook & Sion Catalog. https://arxiv.org/abs/astro-ph/0503107

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