8 papers · 1 filter
Driving in ZZ Ceti stars - Problem solved?
A. Kim, D. E. Winget, M. H. Montgomery +1
There is a fairly tight correlation between the pulsation periods and effective temperatures of ZZ Ceti stars (cooler stars have longer periods). This seems to fit the theoretical…
Eleven New DAVs from the Sloan Survey
F. Mullally, S. E. Thompson, B. G. Castanheira +5
We report the discovery of eleven new variable DA white dwarf (ZZ Ceti) stars. Candidates were selected by deriving temperatures from model fits to spectra obtained from the Sloan…
White Dwarfs in Open Clusters: Calibrating the Clock
T. von Hippel, D. E. Winget, W. H. Jefferys +1
We present an update of our on-going effort to improve the precision of white dwarf cosmochronology via careful analyses of white dwarf photometry in open clusters. To improve the…
The White Dwarf Luminosity Function: The Shape of Things to Come
T. von Hippel, M. Kilic, J. Munn +10
We describe a new survey for cool white dwarfs that supplements Sloan Digital Sky Survey photometry with USNO proper motions and follow-up spectroscopy. To date we have discovered…
Identification of Cool White Dwarfs in the NOAO Deep Wide-Field Survey
M. Kilic, D. E. Winget, T. von Hippel +1
We report our search for the cool white dwarfs belonging to the Galactic disk by extending the NOAO Deep Wide-Field Survey. Narrow-band DDO51 photometry of the Deep Wide-Field Surv…
Search For Oxygen in Cool DQ White Dwarf Atmospheres
M. Kilic, D. E. Winget, T. von Hippel +2
We report new infrared spectroscopic observations of cool DQ white dwarfs by using Coolspec on the 2.7m Harlan-Smith Telescope. DQs have helium-rich atmospheres with traces of mole…