378 citations · 5k across the 96 of their papers we have counts for
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Mean ZZ Ceti pulsation period gauges stellar temperature
Anjum S. Mukadam, M. H. Montgomery, A. Kim +3
The mean pulsation period of ZZ Ceti stars increases with decreasing effective temperature as we traverse from the blue to the red edge of the instability strip. This well-establis…
New Techniques to Determine Ages of Open Clusters Using White Dwarfs
E. J. Jeffery, T. von Hippel, W. H. Jefferys +3
Currently there are two main techniques for independently determining the ages of stellar populations: main sequence evolution theory (via cluster isochrones) and white dwarf cooli…
A Spitzer White Dwarf Infrared Survey
F. Mullally, Mukremin Kilic, William T. Reach +4
We present mid-infrared photometry of 124 white dwarf stars with Spitzer Space Telescope. Objects were observed simultaneously at 4.5 and 8.0um with sensitivities better than 1 mJy…
Towards a pure ZZ Ceti instability strip
B. G. Castanheira, S. O. Kepler, A. F. M. Costa +8
We have observed again two stars inside the ZZ Ceti instability strip that were previously classified as not-observed-to-vary (NOV) by Mukadam et al. (2004) and found them to be lo…
Spitzer White Dwarf Planet Limits
F. Mullally, Ted von Hippel, D. E. Winget
We present preliminary limits on the presence of planets around white dwarf stars using the IRAC photometer on the Spitzer space telescope. Planets emit strongly in the mid-infrare…
Further Evidence for Variable Synchrotron Emission in XTE J1118+480 in Outburst
R. I. Hynes, E. L. Robinson, K. J. Pearson +7
We present simultaneous multicolor infrared and optical photometry of the black hole X-ray transient XTE J1118+480 during its short 2005 January outburst, supported by simultaneous…
Debris Disks Around White Dwarfs: The DAZ Connection
Mukremin Kilic, Ted von Hippel, S. K. Leggett +1
We present near-infrared spectroscopic observations of 20 previously known DAZ white dwarfs obtained at the NASA Infrared Telescope Facility. Two of these white dwarfs (G29-38 and…
Inverting Color-Magnitude Diagrams to Access Precise Star Cluster Parameters: A Bayesian Approach
Ted von Hippel, William H. Jefferys, James Scott +5
We demonstrate a new Bayesian technique to invert color-magnitude diagrams of main sequence and white dwarf stars to reveal the underlying cluster properties of age, distance, meta…
The Mystery Deepens: Spitzer Observations of Cool White Dwarfs
Mukremin Kilic, Ted von Hippel, Fergal Mullally +4
We present 4.5m and 8m photometric observations of 18 cool white dwarfs obtained with the Spitzer Space Telescope. Our observations demonstrate that four white dwarfs with T_…