Search

Now showing items 1-4 of 4

The Physics of Crystallization from Globular Cluster White Dwarf Stars in NGC 6397

Winget, D. E.; Kepler, S. O.; Campos, Fabiola; Montgomery, M. H.; Girardi, Leo; Bergeron, P.; Williams, Kurtis (2009-03)

We explore the physics of crystallization in the deep interiors of white dwarf (WD) stars using the color-magnitude diagram and luminosity function constructed from proper- motion cleaned Hubble Space Telescope photometry ...

SDSS J142625.71+575218.3: A Prototype for A New Class of Variable White Dwarf

Montgomery, M. H.; Williams, Kurtis A.; Winget, D. E.; Dufour, Patrick; DeGennaro, Steven; Liebert, James (2008-05)

We present the results of a search for pulsations in six of the recently discovered carbon-atmosphere white dwarf ("hot DQ") stars. On the basis of our theoretical calculations, the star SDSS J142625.71 + 575218.3 is the ...

Discovery of an Ultramassive Pulsating White Dwarf

Hermes, J. J.; Kepler, S. O.; Castanheira, Barbara G.; Gianninas, A.; Winget, D. E.; Montgomery, M. H.; Brown, Warren R.; Harrold, Samuel T. (2013-07)

We announce the discovery of the most massive pulsating hydrogen-atmosphere white dwarf (WD) ever discovered, GD 518. Model atmosphere fits to the optical spectrum of this star show it is a 12,030 +/- 210 K WD with a log ...

SDSS J184037.78+642312.3: the First Pulsating Extremely Low Mass White Dwarf

Hermes, J. J.; Montgomery, M. H.; Winget, D. E.; Brown, Warren R.; Kilic, Mukremin; Kenyon, Scott J. (2012-05)

We report the discovery of the first pulsating extremely low mass (ELM) white dwarf (WD), SDSS J184037.78+642312.3 (hereafter J1840). This DA (hydrogen-atmosphere) WD is by far the coolest and the lowest-mass pulsating WD, ...