• The pulsation modes of the pre-white dwarf PG 1159-035 

      Costa, J. E. S.; Solheim, Jan Erik; Kepler, S. O.; Winget, D. E.; O’Brien, M. S.; Kawaler, S. D.; Costa, A. F. M.; Giovannini, O.; Kanaan, A.; Mukadam, A. S.; Mullally, F.; Nitta, A.; Provenc, J. L.; Shipman, H.; Wood, M. A.; Ahrens, T. J.; Grauer, A.; Kilic, M.; Bradley, P. A.; Sekiguchi, K.; Crowe, R.; Jiang, X. J.; Sullivan, D.; Sullivan, T.; Rosen, R.; Clemens, J. C.; Janulis, R.; O’Donoghue, D.; Ogloza, W.; Baran, A.; Silvotti, R.; Marinoni, S.; Vauclair, G.; Dolez, N.; Chevreton, M.; Dreizler, S.; Schuh, S.; Deetjen, J.; Nagel, T.; Gonzalez Perez, J. M.; Ulla, A.; Barstow, Martin; Burleigh, M.; Good, S.; Metcalfe, T.S.; Kim, S.-L.; Lee, H.; Sergeev, A.; Akan, M.C.; Çakırlı, Ö.; Paparo, M.; Viraghalmy, G.; Ashoka, B. N.; Handler, G.; Hürkal, Özlem; Johannessen, F.; Kleinman, S. J.; Kalytis, R.; Krzesinski, J.; Klumpe, E.; Larrison, J.; Lawrence, T.; Meištas, E.; Martinez, P.; Nather, R. E.; Fu, J.-N.; Pakštienė, E.; Rosen, R.; Romero-Colmenero, E.; Riddle, R.; Seetha, S.; Silvestri, N. M.; Vučković, M.; Warner, B.; Zola, S.; Althaus, L. G.; Córsico, A. H.; Montgomery, M. H. (Journal article; Tidsskriftartikkel; Peer reviewed, 2008)
      Context. PG 1159-035, a pre-white dwarf with Teff ≃ 140 000 K, is the prototype of both two classes: the PG 1159 spectroscopic class and the DOV pulsating class. Previous studies of PG 1159-035 photometric data obtained with the Whole Earth Telescope (WET) showed a rich frequency spectrum allowing the identification of 122 pulsation modes. Analyzing the periods of pulsation, it is possible to ...
    • Understanding the Cool DA White Dwarf Pulsator, G29–38 

      Solheim, Jan Erik; Kleinman, S. J.; Bruvold, A.; Nather, R. E.; Winget, D. E.; Clemens, J. C.; Bradley, A.; Kanaan, A.; Claver, C. F.; Watson, T. K.; Yanagida, K.; Nitta, A.; Dixson, J. S.; Grauer, A. D.; Hine, B. P.; Fontaine, G.; Liebert, James; Sullivan, D. J.; Wickramasinghe, D. T.; Achilleos, N.; Mara, T. M. K.; Seetha, S.; Ashoka, B. N.; Leibowitz, E. M.; Moskalik, P.; Krzesi´nski, J.; O’Donoghue, D.; Kurtz, D. W.; Warner, B.; Martinez, Peter; Dolez, N.; Chevreton, M.; Barstow, M. A.; Kepler, S. O.; Giovannini, O.; Hansen, C. J.; Augusteijn, T. (Journal article; Tidsskriftartikkel; Peer reviewed, 1997-10-10)
      The white dwarfs are promising laboratories for the study of cosmochronology and stellar evolution. Through observations of the pulsating white dwarfs, we can measure their internal structures and compositions, critical to understanding post main sequence evolution, along with their cooling rates, allowing us to calibrate their ages directly. The most important set of white dwarf variables to ...