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Strong Limits on the DFSZ Axion Mass with G117-B15A
We compute rates of period change () for the 215 s mode in G117-B15A and the 213 s mode in R548, first for models without axions, and then for models with axions of increasing mass. We use theExpand
A deep test of radial differential rotation in a helium-atmosphere white dwarf: I. Discovery of pulsations in PG 0112+104
We present the detection of non-radial oscillations in a hot, helium-atmosphere white dwarf using 78.7 d of nearly uninterrupted photometry from the Kepler space telescope. With an effectiveExpand
Fine Grid Asteroseismology Of G117-B15A And R548
We now have a good measurement of the cooling rate of G117-B15A. In the near future, we will have equally well determined cooling rates for other pulsating white dwarfs, including R548. The abilityExpand
KIC 4552982: Outbursts and Asteroseismology from the Longest Pseudo-Continuous Light Curve of a ZZ Ceti
We present the Kepler light curve of KIC 4552982, the first ZZ Ceti (hydrogen-atmosphere pulsating white dwarf star) discovered in the Kepler field of view. Our data span more than 1.5 years with aExpand
Measuring the evolutionary rate of cooling of ZZ Ceti
We have finally measured the evolutionary rate of cooling of the pulsating hydrogen atmosphere (DA) white dwarf ZZ Ceti (Ross 548), as reflected by the drift rate of the 213.13260694 s period. UsingExpand
Insights into internal effects of common-envelope evolution using the extended Kepler mission
We present an analysis of the binary and physical parameters of a unique pulsating white dwarf with a main-sequence companion, SDSS J1136+0409, observed for more than 77 d during the first pointingExpand
A New Timescale for Period Change in the Pulsating DA White Dwarf WD 0111+0018
We report the most rapid rate of period change measured to date for a pulsating DA (hydrogen atmosphere) white dwarf (WD), observed in the 292.9 s mode of WD 0111+0018. The observed period change,Expand
Asteroseismology of the Kepler Field DBV White Dwarf. It is a Hot One
We present an asteroseismic analysis of the helium atmosphere white dwarf (a DBV) recently found in the field of view of the Kepler satellite. We analyze the five-mode pulsation spectrum that wasExpand
Asteroseismology of the Kepler V777 Herculis variable white dwarf with fully evolutionary models
Context. DBV stars are pulsating white dwarfs with atmospheres rich in He. Asteroseismology of DBV stars can provide valuable clues about the origin, structure and evolution of hydrogen-deficientExpand
WDEC - A code for modeling white dwarf structure and pulsations
The White Dwarf Evolution Code (WDEC), written in Fortran, makes models of white dwarf stars. Expand