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Measuring The Evolutionary Rate Of Cooling Of ZZ Ceti

Mukadam, Anjum S.; Bischoff-Kim, Agnes; Fraser, Oliver; Corsico, A. H.; Montgomery, Michael H.; Kepler, S. O.; Romero, A. D.; Winget, D. E.; Hermes, J. J.; Riecken, T. S.; Kronberg, M. E.; Winget, K. I.; Falcon, Ross E.; Chandler, Dean W.; Kuehne, J. W.; Sullivan, Denis J.; Reaves, D.; von Hippel, Ted; Mullally, Fergal; Shipman, H.; Thompson, Susan E.; Silvestri, N. M.; Hynes, Robert I. (2013-07)

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. Using 41 yr of time-series ...

Photometric Variability In A Warm, Strongly Magnetic Dq White Dwarf, SDSS J103655.39+652252.2

Williams, Kurtis A.; Winget, D. E.; Montgomery, Michael H.; Dufour, Patrick; Kepler, S. O.; Hermes, J. J.; Falcon, Ross E.; Winget, K. I.; Bolte, Michael; Rubin, Kate H. R.; Liebert, James (2013-06)

We present the discovery of photometric variability in the DQ white dwarf SDSS J103655.39+652252.2 (SDSS J1036+6522). Time-series photometry reveals a coherent monoperiodic modulation at a period of 1115.64751(67) s with ...

Enigmatic Recurrent Pulsational Variability Of The Accreting White Dwarf EQ LYN (Sdss J074531.92+453829.6)

Mukadam, Adam S.; Townsley, D. M.; Szkody, Paula; Gaansicke, B. T.; Southworth, J.; Brockett, T.; Parsons, S.; Hermes, J. J.; Montgomery, M. H.; Winget, D. E.; Harrold, S.; Tovmassian, G.; Zharikov, S.; Drake, A. J.; Henden, A.; Rodriguez-Gil, P.; Sion, E. M.; Zola, S.; Szymanski, T.; Pavlenko, E.; Aungwerojwit, A.; Qian, S. B. (2013-09)

Photometric observations of the cataclysmic variable EQ Lyn (SDSS J074531.92+453829.6), acquired from 2005 October to 2006 January, revealed high-amplitude variability in the range 1166-1290 s. This accreting white dwarf ...

A Gravitational Redshift Determination Of The Mean Mass Of DBA White Dwarfs

Falcon, R. E.; Winget, D. E.; Montgomery, M. H.; Williams, K. A. (2010-08)

We measure apparent velocities (v(app)) of the H alpha and H beta Balmer line cores for 16 helium-dominated white dwarfs (WDs) using optical spectra taken for the European Southern Observatory SN Ia progenitor survey (SPY). ...

Radius Constraints From High-Speed Photometry Of 20 Low-Mass White Dwarf Binaries

Hermes, J. J.; Brown, Warren R.; Kilic, Mukremin; Gianninas, A.; Chote, Paul; Sullivan, Denis J.; Winget, D. E.; Bell, Keaton J.; Falcon, Ross E.; Winget, K. I.; Mason, Paul A.; Harrold, Samuel T.; Montgomery, Michael H. (2014-09)

We carry out high-speed photometry on 20 of the shortest-period, detached white dwarf binaries known and discover systems with eclipses, ellipsoidal variations (due to tidal deformations of the visible white dwarf), and ...

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 ...

Discovery of A ZZ Ceti in the Kepler Mission Field

Hermes, J. J.; Mullally, Fergal; Ostensen, R. H.; Williams, Kurtis A.; Telting, John; Southworth, John; Bloemen, S.; Howell, Steve B.; Everett, Mark; Winget, D. E. (2011-11)

We report the discovery of the first identified pulsating DA white dwarf, WD J1916+3938 (Kepler ID 4552982), in the field of the Kepler mission. This ZZ Ceti star was first identified through ground-based, time-series ...

Discovery Of A New AM CVn System With The Kepler Satellite

Fontaine, G.; Brassard, P.; Green, E. M.; Charpinet, S.; Dufour, Patrick; Hubeny, I.; Steeghs, D.; Aerts, C.; Randall, S. K.; Bergeron, P.; Guvenen, B.; O'Malley, C. J.; Van Grootel, V.; Ostensen, R. H.; Bloemen, S.; Silvotti, R.; Howell, Steve B.; Baran, A.; Kepler, S. O.; Marsh, T. R.; Montgomery, Michael H.; Oreiro, R.; Provencal, J.; Telting, J.; Winget, D. E.; Zima, W.; Christensen-Dalsgaard, J.; Kjeldsen, H. (2011-01)

We report the discovery of a new AM CVn system on the basis of broadband photometry obtained with the Kepler satellite supplemented by ground-based optical spectroscopy. Initially retained on Kepler target lists as a ...

Creating White Dwarf Photospheres In The Laboratory

Falcon, R. E.; Rochau, G. A.; Bailey, J. E.; Ellis, J. L.; Montgomery, M. H.; Winget, D. E.; Gomez, M. R.; Leeper, R. J. (2010-08)

We present a preliminary report from the laboratory astrophysics experiments to create macroscopic (similar to 19 cm(3)) hydrogen-plasmas with white dwarf (WD) photospheric conditions (i.e., temperature, electron density). ...

A Dark Spot On A Massive White Dwarf

Kilic, Mukremin; Gianninas, Alexandros; Bell, Keaton J.; Curd, Brandon; Brown, Warren R.; Hermes, J. J.; Dufour, P.; Wisniewski, J. Patrick; Winget, D. E.; Winget, K. I. (2015-12)

We present the serendipitous discovery of eclipse-like events around the massive white dwarf SDSS J152934.98+292801.9 (hereafter J1529+2928). We selected J1529+2928 for time-series photometry based on its spectroscopic ...