Navegação Produção Científica por Autor "Wood, Matthew A."

Resultados 1-20 de 27

    • Amplitude and frequency variability of the pulsating DB white dwarf stars KUV 05134+2605 and PG 1654+160 observed with the Whole Earth Telescope 

      Handler, Gerald; O'Donoghue, Darragh; Muller, M.; Solheim, Jan-Eric; Gonzalez Perez, Jose Miguel; Johannessen, F.; Paparo, Margit; Szeidl, Bela; Virághalmy, Géza; Silvotti, Roberto; Vauclair, Gérard; Dolez, Noël; Pallier, E.; Chevreton, Michel; Kurtz, Donald W.; Bromage, Gordon E.; Cunha, Margarida S.; Ostensen, Roy; Fraga, Luciano; Kanaan Neto, Antonio Nemer; Amorim, André; Giovannini Junior, Odilon; Kepler, Souza Oliveira; Costa, Alex Fabiano Murillo da; Anderson, R.F.; Wood, Matthew A.; Silvestri, Nicole M.; Klumpe, Eric W.; Carlton, Robert F.; Miller, Hugh Richard; McFarland, John P.; Grauer, Albert D.; Kawaler, Steven D.; Riddle, Reed L.; Reed, M. D.; Nather, R. Edward; Winget, Donald Earl; Hill, J.A.; Metcalfe, Travis S.; Mukadam, Anjum Shagufta; Kilic, Mukremin; Watson, Todd K.; Kleinman, Scot James; Nitta, Atsuko; Guzik, Joyce Ann; Bradley, Paul A.; Sekiguchi, Kazuhiro; Sullivan, Denis J.; Sullivan, Terry; Shobbrook, Robert R.; Jiang, Xiaojun; Birch, P.; Ashoka, B.N.; Seetha, S.; Girish, V.; Joshi, Santosh; Dorokhova, Tatyana N.; Dorokhov, N.I.; Akan, Mustafa Can; Meistas, Edmundas G.; Janulis, Rimvydas; Kalytis, Romualdas; Alisauskas, Darius; Anguma, S.K.; Kalebwe, P.C.; Moskalik, Pawel; Ogloza, Waldemar; Stachowski, G.; Pajdosz, Gabriel; Zola, Staszek (2003) [Artigo de periódico]
      We have acquired new time series photometry of the two pulsating DB white dwarf stars KUV 05134+2605 and PG 1654+160 with the Whole Earth Telescope. Additional single-site photometry is also presented. We use all these ...

    • Asteroseismology of a star cooled by neutrino emission : the pulsating pre-white dwarf PG 0122+200 

      O'Brien, M. Sean; Vauclair, Gérard; Kawaler, Steven D.; Watson, Todd K.; Winget, Donald Earl; Nather, R. Edward; Montgomery, Michael Houston; Nitta, Atsuko; Kleinman, Scot James; Sullivan, Denis J.; Jiang, Xiaojun; Marar, T.M. Krishnan; Seetha, S.; Ashoka, B.N.; Bhattacharya, J.; Leibowitz, Elia M.; Hemar, Shirley; Ibbetson, Peter A.; Warner, B.; Van Zyl, L.; Moskalik, Pawel; Zola, Staszek; Pajdosz, Gabriel; Krzesinski, Jerzy; Dolez, Noël; Chevreton, Michel; Solheim, Jan-Eric; Thomassen, T.; Kepler, Souza Oliveira; Giovannini Junior, Odilon; Provencal, Judith L.; Wood, Matthew A.; Clemens, J. Christopher (1998) [Artigo de periódico]
      Observation of g-mode pulsations in the variable pre-white dwarf (GW Virginis) stars provides a unique means to probe their interiors and to study the late stages of stellar evolution. Multisite campaigns have in several ...

    • Asteroseismology of RXJ 2117+3412, the hottest pulsating PG 1159 star 

      Vauclair, Gérard; Moskalik, Pawel; Pfeiffer, Ben; Chevreton, Michel; Dolez, Noël; Serre, B.; Kleinman, Scot James; Barstow, Martin A.; Sansom, A.E.; Solheim, Jan-Eric; Belmonte, J.A.; Kawaler, Steven D.; Kepler, Souza Oliveira; Kanaan Neto, Antonio Nemer; Giovannini Junior, Odilon; Winget, Donald Earl; Watson, Todd K.; Nather, R. Edward; Clemens, J. Christopher; Provencal, Judith L.; Dixson, James S.; Yanagida, K.; Nitta, Atsuko; Montgomery, Michael Houston; Klumpe, Eric W.; Bruvold, A.; O'Brien, M. Sean; Hansen, Carl J.; Grauer, Albert D.; Bradley, Paul A.; Wood, Matthew A.; Achilleos, Nicholas; Jiang, Shi Yang; Fu, Jianning Ning; Marar, T.M. Krishnan; Ashoka, B.N.; Meistas, Edmundas G.; Chernyshev, A.V.; Mazeh, Tsevi; Leibowitz, Elia M.; Hemar, Shirley; Krzesinski, Jerzy; Pajdosz, Gabriel; Zola, Staszek (2002) [Artigo de periódico]
      The pulsating PG 1159 planetary nebula central star RXJ 2117+3412 has been observed over three successive seasons of a multisite photometric campaign. The asteroseismological analysis of the data, based on the 37 identified ...

    • Asteroseismology of the dov star PG 1159-035 with the Whole Earth Telescope 

      Winget, Donald Earl; Hansen, Carl J.; Fontaine, Gilles; Achilleos, Nicholas; Wickramasinghe, D.T.; Marar, T.M. Krishnan; Seetha, S.; Ashoka, B.N.; O'Donoghue, Darragh; Warner, B.; Kurtz, Donald W.; Buckley, David A.H.; Brickhill, J.; Vauclair, Gérard; Dolez, Noël; Chevreton, Michel; Barstow, Martin A.; Solheim, Jan-Eric; Kanaan Neto, Antonio Nemer; Hine, B.P.; Grauer, Albert D.; Frueh, M.L.; Claver, C.F.; Wood, Matthew A.; Bradley, Paul A.; Kleinman, Scot James; Provencal, Judith L.; Clemens, J. Christopher; Nather, R. Edward (1991) [Artigo de periódico]
      We report the results from 264.1 hr of nearly continuous time-series photometry on the pulsating pre-white dwarf star (DOV) PG 1159-035. The high-resolution power spectrum of this data set is dominated by power in the range ...

    • Constraining the evolution of ZZ Ceti 

      Mukadam, Anjum Shagufta; Kepler, Souza Oliveira; Winget, Donald Earl; Nather, R. Edward; Kilic, Mukremin; Mullally, Fergal; Von Hippel, Theodore A.; Kleinman, Scot James; Nitta, Atsuko; Guzik, Joyce Ann; Bradley, Paul A.; Matthews, Jaymie M.; Sekiguchi, Kazuhiro; Sullivan, Denis J.; Sullivan, Terry; Shobbrook, Robert R.; Birch, P.; Jiang, Xiaojun; Xu, D.W.; Joshi, Santosh; Ashoka, B.N.; Ibbetson, Peter A.; Leibowitz, Elia M.; Ofek, Eran O.; Meistas, Edmundas G.; Janulis, Rimvydas; Alisauskas, Darius; Kalytis, Romualdas; Handler, Gerald; Kilkenny, Dave; O'Donoghue, Darragh; Kurtz, Donald W.; Muller, M.; Moskalik, Pawel; Ogloza, Waldemar; Zola, Staszek; Krzesinski, Jerzy; Johannessen, F.; Gonzalez Perez, Jose Miguel; Solheim, Jan-Eric; Silvotti, Roberto; Bernabei, S.; Vauclair, Gérard; Dolez, Noël; Fu, Jianning Ning; Chevreton, Michel; Manteiga, Minia; Suarez, Olga; Ulla, Ana; Cunha, Margarida S.; Metcalfe, Travis S.; Kanaan Neto, Antonio Nemer; Fraga, Luciano; Costa, Alex Fabiano Murillo da; Giovannini Junior, Odilon; Fontaine, Gilles; Bergeron, Pierre; O'Brien, M. Sean; Sanwal, Divas; Wood, Matthew A.; Ahrens, T.J.; Silvestri, Nicole M.; Klumpe, Eric W.; Kawaler, Steven D.; Riddle, Reed L.; Reed, M. D.; Watson, Todd K. (2003) [Artigo de periódico]
      We report our analysis of the stability of pulsation periods in the DAV star (pulsating hydrogen atmosphere white dwarf ) ZZ Ceti, also called R548. On the basis of observations that span 31 years, we conclude that the ...

    • Delta Scuti Network observations of XX Pyx : detection of 22 pulsation modes and of short-term amplitude and frequency variations 

      Handler, Gerald; Arentoft, T.; Shobbrook, Robert R.; Wood, Matthew A.; Crause, L.A.; Crake, P.; Podmore, F.; Habanyama, A.; Oswalt, T.; Birch, P.; Lowe, G.; Sterken, C.; Meintjes, P.; Brink, J.; Claver, C.F.; Medupe, R.; Guzik, Joyce Ann; Beach, T.E.; Martinez, Peter; Leibowitz, Elia M.; Ibbetson, Peter A.; Smith, T.; Ashoka, B.N.; Raj, N.E.; Kurtz, Donald W.; Balona, L.A.; O'Donoghue, Darragh; Costa, Jose Eduardo da Silveira; Breger, M. (2000) [Artigo de periódico]
      We report multisite observations devoted to the main-sequence δ Scuti star XX Pyx, conducted as the 17th run of the Delta Scuti Network. Over 125 nights a total of 550 h of usable time-series photometric B- and V-filter ...

    • A detection of the evolutionary time scale of the da white dwarf G117-B15A with the Whole Earth Telescope 

      Kepler, Souza Oliveira; Winget, Donald Earl; Nather, R. Edward; Bradley, Paul A.; Grauer, Albert D.; Fontaine, Gilles; Bergeron, Pierre; Vauclair, Gérard; Claver, C.F.; Marar, T.M. Krishnan; Seetha, S.; Ashoka, B.N.; Mazeh, Tsevi; Leibowitz, Elia M.; Dolez, Noël; Chevreton, Michel; Barstow, Martin A.; Clemens, J. Christopher; Kleinman, Scot James; Sansom, A.E.; Tweedy, R.W.; Hine, B.P.; Provencal, Judith L.; Wesemael, F.; Wood, Matthew A.; Brassard, P.; Solheim, Jan-Eric; Emanuelsen, P.-I.; Kanaan Neto, Antonio Nemer; Kepler, Souza Oliveira (1991) [Artigo de periódico]
      We have detected the time rate of change for the main pulsation period of the 13,000 K DA white dwarf G117-B15A, using the Whole Earth Telescope (WET). The observed rate of period change, P = (12.0 ± 3.5) x 10- 15 s s - ...

    • Discovery of the 'missing' mode in HR 1217 by the Whole Earth Telescope 

      Kurtz, Donald W.; Kawaler, Steven D.; Riddle, Reed L.; Reed, M. D.; Cunha, Margarida S.; Wood, Matthew A.; Silvestri, Nicole M.; Watson, Todd K.; Dolez, Noël; Moskalik, Pawel; Zola, Staszek; Pallier, E.; Guzik, Joyce Ann; Metcalfe, Travis S.; Mukadam, Anjum Shagufta; Nather, R. Edward; Winget, Donald Earl; Sullivan, Denis J.; Sullivan, Terry; Sekiguchi, Kazuhiro; Jiang, Xiaojun; Shobbrook, Robert R.; Ashoka, B.N.; Seetha, S.; Joshi, Santosh; O'Donoghue, Darragh; Handler, Gerald; Mueller, M.; Gonzalez Perez, Jose Miguel; Solheim, Jan-Eric; Johannessen, F.; Ulla, Ana; Kepler, Souza Oliveira; Kanaan Neto, Antonio Nemer; Costa, Alex Fabiano Murillo da; Fraga, Luciano; Giovannini Junior, Odilon; Matthews, Jaymie M.; WET collaboration (2002) [Artigo de periódico]
      HR1217 is a prototypical rapidly oscillating Ap star that has presented a test to the theory of non-radial stellar pulsation. Prior observations showed a clear pattern of five modes with alternating frequency spacings of ...

    • Empirical determination of convection parameters in white dwarfs. I. Whole earth telescope obsevations of EC14012-1446 

      Provencal, Judith L.; Montgomery, Michael Houston; Kanaan Neto, Antonio Nemer; Thompson, S. E.; Dalessio, J.; Shipman, Harry L.; Childers, D.; Clemens, J. Christopher; Rosen, Rachel; Henrique, P.; Bischoff-Kim, Agnès; Strickland, Willie; Chandler, Dean W.; Walter, B.; Watson, Todd K.; Castanheira, Bárbara Garcia; Wang, Siqiu; Handler, Gerald; Wood, Matthew A.; Vennes, S.; Nemeth, Peter; Kepler, Souza Oliveira; Reed, M. D.; Nitta, Atsuko; Kleinman, Scot James; Brown, Tim; Kim, Seung-Lee; Sullivan, Denis J.; Chen, Wen-Ping; Yang, M.; Shih, Chia-You; Jiang, Xiaojun; Sergeev, A.; Maksim, A.; Janulis, Rimvydas; Baliyan, Kiran S.; Vats, Hari Om; Zola, Staszek; Baran, Andrzej; Winiarski, M.; Ogloza, Waldemar; Paparo, Margit; Baran, Andrzej; Bognár, Zsófia; Papics, P.; Kilkenny, Dave; Sefako, R.; Buckley, David A.H.; Loaring, N.; Kniazev, A.; Silvotti, Roberto; Galleti, S.; Nagel, Thorsten; Vauclair, Gérard; Dolez, Noël; Fremy, J. R.; Gonzalez Perez, Jose Miguel; Almenara, J. M.; Fraga, Luciano (2012) [Artigo de periódico]
      We report on an analysis of 308.3 hr of high-speed photometry targeting the pulsating DA white dwarf EC14012-1446. The datawere acquiredwith theWhole Earth Telescope during the 2008 international observing run XCOV26. The ...

    • New whole earth telescope observations of cd-247599 : steps towards delta scuti star seismology 

      Handler, Gerald; Pikall, H.; O'Donoghue, Darragh; Buckley, David A.H.; Vauclair, Gérard; Chevreton, Michel; Giovannini Junior, Odilon; Kepler, Souza Oliveira; Goode, P.R.; Provencal, Judith L.; Wood, Matthew A.; Clemens, J. Christopher; O'Brien, M. Sean; Nather, R. Edward; Winget, Donald Earl; Kleinman, Scot James; Kanaan Neto, Antonio Nemer; Watson, Todd K.; Nitta, Atsuko; Montgomery, Michael Houston; Klumpe, Eric W.; Bradley, Paul A.; Sullivan, Denis J.; Wu, K.; Marar, T.M. Krishnan; Seetha, S.; Ashoka, B.N.; Mahra, H.S.; Bhat, B.C.; Babu, V.C.; Leibowitz, Elia M.; Hemar, Shirley; Ibbetson, Peter A.; Mashal, E.; Meistas, Edmundas G.; Dziembowski, W.A.; Pamyantnykh, A.A.; Moskalik, Pawel; Zola, Staszek; Pajdosz, Gabriel; Krzesinski, Jerzy; Solheim, Jan-Eric; Bard, S.; Massarand, C.M.; Breger, M.; Gelbmann, M.J.; Paunzen, E.; North, P. (1997) [Artigo de periódico]
      92 h of new Whole Earth Telescope observations have been acquired for the δ Scuti star CD -24 7599. All the seven pulsation modes reported by Handler et al. are confirmed. However, significant amplitude variations which ...

    • Normal modes and discovery of high-order cross-frequencies in the DBV white dwarf GD 358 

      Vuille, F.; O'Donoghue, Darragh; Buckley, David A.H.; Massacand, C.N.; Solheim, Jan-Eric; Bard, S.; Vauclair, Gérard; Giovannini Junior, Odilon; Kepler, Souza Oliveira; Kanaan Neto, Antonio Nemer; Provencal, Judith L.; Wood, Matthew A.; Clemens, J. Christopher; Kleinman, Scot James; O'Brien, M. Sean; Nather, R. Edward; Winget, Donald Earl; Nitta, Atsuko; Klumpe, Eric W.; Montgomery, Michael Houston; Watson, Todd K.; Bradley, Paul A.; Sullivan, Denis J.; Wu, K.; Marar, T.M. Krishnan; Seetha, S.; Ashoka, B.N.; Mahra, H.S.; Bhat, B.C.; Babu, V.C.; Leibowitz, Elia M.; Hemar, Shirley; Ibbetson, Peter A.; Mashal, E.; Meistas, Edmundas G.; Moskalik, Pawel; Zola, Staszek; Krzesinski, Jerzy; Pajdosz, Gabriel (2000) [Artigo de periódico]
      We present a detailed mode identification performed on the 1994 Whole Earth Telescope (WET) run on GD 358. The results are compared with that obtained for the same star from the 1990 WET data. The two temporal spectra show ...

    • Observational limits on companions to g29-38 

      Kleinman, Scot James; Nather, R. Edward; Winget, Donald Earl; Clemens, J. Christopher; Bradley, Paul A.; Kanaan Neto, Antonio Nemer; Provencal, Judith L.; Claver, C.F.; Watson, Todd K.; Yanagida, K.; Dixson, James S.; Wood, Matthew A.; Sullivan, Denis J.; Meistas, Edmundas G.; Leibowitz, Elia M.; Moskalik, Pawel; Zola, Staszek; Pajdosz, Y.; Krzesinski, Jerzy; Solheim, Jan-Eric; Bruvold, A.; O'Donoghue, Darragh; Katz, M.; Vauclair, Gérard; Dolez, Noël; Chevreton, Michel; Barstow, Martin A.; Kepler, Souza Oliveira; Giovannini Junior, Odilon; Hansen, Carl J.; Kawaler, Steven D. (1994) [Artigo de periódico]
      Recent interest in the variable (DAV) white dwarf G29-38 has been stirred by a tentative report of a radial velocity variation that may be due to an unseen companion. Earlier evidence for a brown dwarf in the system has ...

    • Observations of the pulsating white dwarf G 185-32 

      Castanheira, Bárbara Garcia; Kepler, Souza Oliveira; Moskalik, Pawel; Zola, Staszek; Pajdosz, Gabriel; Krzesinski, Jerzy; O'Donoghue, Darragh; Katz, M.; Buckley, David A.H.; Vauclair, Gérard; Dolez, Noël; Chevreton, Michel; Barstow, Martin A.; Kanaan Neto, Antonio Nemer; Giovannini Junior, Odilon; Provencal, Judith L.; Kawaler, Steven D.; Clemens, J. Christopher; Nather, R. Edward; Winget, Donald Earl; Watson, Todd K.; Yanagida, K.; Dixson, James S.; Hansen, Carl J.; Bradley, Paul A.; Wood, Matthew A.; Sullivan, Denis J.; Kleinman, Scot James; Meistas, Edmundas G.; Solheim, Jan-Eric; Bruvold, A.; Leibowitz, Elia M.; Mazeh, Tsevi; Koester, D.; Montgomery, Michael Houston (2004) [Artigo de periódico]
      We observed the pulsating hydrogen atmosphere white dwarf G 185–32 with the Whole Earth Telescope in 1992. We report on a weighted Fourier transform of the data detecting 18 periodicities in its light curve. Using the ...

    • Pushing the ground-based limit : 14-μmag photometric precision with the definitive Whole Earth Telescope asteroseismic data set for the rapidly oscillating Ap star HR 1217 

      Kurtz, Donald W.; Cameron, C.; Cunha, Margarida S.; Dolez, Noël; Vauclair, Gérard; Pallier, E.; Ulla, Ana; Kepler, Souza Oliveira; Costa, Alex Fabiano Murillo da; Kanaan Neto, Antonio Nemer; Fraga, Luciano; Giovannini Junior, Odilon; Wood, Matthew A.; Silvestri, Nicole M.; Kawaler, Steven D.; Riddle, Reed L.; Reed, M. D.; Watson, Todd K.; Metcalfe, Travis S.; Mukadam, Anjum Shagufta; Nather, R. Edward; Winget, Donald Earl; Nitta, Atsuko; Kleinman, Scot James; Guzik, Joyce Ann; Bradley, Paul A.; Matthews, Jaymie M.; Sekiguchi, Kazuhiro; Sullivan, Denis J.; Sullivan, Terry; Shobbrook, Robert R.; Jiang, Xiaojun; Birch, P.; Ashoka, B.N.; Seetha, S.; Girish, V.; Joshi, Santosh; Moskalik, Pawel; Zola, Staszek; O'Donoghue, Darragh; Handler, Gerald; Mueller, M.; Gonzalez Perez, Jose Miguel; Solheim, Jan-Eric; Johannessen, F.; Bigot, L. (2005) [Artigo de periódico]
      HR1217 is one of the best-studied rapidly oscillating Ap (roAp) stars, with a frequency spectrum of alternating even-and odd-l modes that are distorted by the presence of a strong, global magnetic field. Several recent ...

    • The everchanging pulsating white dwarf GD358 

      Kepler, Souza Oliveira; Nather, R. Edward; Winget, Donald Earl; Nitta, Atsuko; Kleinman, Scot James; Metcalfe, Travis S.; Sekiguchi, Kazuhiro; Jiang, Xiaojun; Sullivan, Denis J.; Sullivan, Terry; Janulis, Rimvydas; Meistas, Edmundas G.; Kalytis, Romualdas; Krzesinski, Jerzy; Ogloza, Waldemar; Zola, Staszek; O'Donoghue, Darragh; Romero-Colmenero, Encarni; Martinez, Peter; Dreizler, Stefan; Deetjen, Jochen L.; Nagel, Thorsten; Schuh, Sonja L.; Vauclair, Gérard; Fu, Jianning Ning; Chevreton, Michel; Solheim, Jan-Eric; Gonzalez Perez, Jose Miguel; Johannessen, F.; Kanaan Neto, Antonio Nemer; Costa, Jose Eduardo da Silveira; Costa, Alex Fabiano Murillo da; Wood, Matthew A.; Silvestri, Nicole M.; Ahrens, T.J.; Jones, Aaron Kyle; Collins, A.E.; Boyer, M.; Shaw, James Scott; Mukadam, Anjum Shagufta; Klumpe, Eric W.; Larrison, Jesse; Kawaler, Steven D.; Riddle, Reed L.; Ulla, Ana; Bradley, Paul A. (2003) [Artigo de periódico]
      We report 323 hours of nearly uninterrupted time series photometric observations of the DBV star GD 358 acquired with the Whole Earth Telescope (WET) during May 23rd to June 8th, 2000. We acquired more than 232 000 independent ...

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

      Costa, Jose Eduardo da Silveira; Kepler, Souza Oliveira; Winget, Donald Earl; O'Brien, M. Sean; Kawaler, Steven D.; Costa, Alex Fabiano Murillo da; Giovannini Junior, Odilon; Kanaan Neto, Antonio Nemer; Mukadam, Anjum Shagufta; Mullally, Fergal; Nitta, Atsuko; Provencal, Judith L.; Shipman, Harry L.; Wood, Matthew A.; Ahrens, T.J.; Grauer, Albert D.; Kilic, Mukremin; Bradley, Paul A.; Sekiguchi, Kazuhiro; Crowe, Richard A.; Jiang, Xiaojun; Sullivan, Denis J.; Sullivan, Terry; Rosen, Rachel; Clemens, J. Christopher; Janulis, Rimvydas; O'Donoghue, Darragh; Ogloza, Waldemar; Baran, Andrzej; Silvotti, Roberto; Marinoni, S.; Vauclair, Gérard; Dolez, Noël; Chevreton, Michel; Dreizler, Stefan; Schuh, Sonja L.; Deetjen, Jochen L.; Nagel, Thorsten; Solheim, Jan-Eric; Gonzalez Perez, Jose Miguel; Ulla, Ana; Barstow, Martin A.; Burleigh, Matt; Good, Simon A.; Metcalfe, Travis S.; Kim, Seung-Lee; Lee, H.; Sergeev, A.; Akan, Mustafa Can; Cakirli, Ö; Paparo, Margit; Virághalmy, Géza; Ashoka, B.N.; Handler, Gerald; Hürkal, Özlem; Johannessen, F.; Kleinman, Scot James; Kalytis, Romualdas; Krzesinski, Jerzy; Klumpe, Eric W.; Larrison, Jesse; Lawrence, T.; Meistas, Edmundas G.; Martinez, Peter; Nather, R. Edward; Fu, Jianning Ning; Pakstiene, Erika; Rosen, R.; Romero-Colmenero, Encarni; Riddle, Reed L.; Seetha, S.; Silvestri, Nicole M.; Vuckovic, Maja; Warner, B.; Zola, Staszek; Althaus, Leandro Gabriel; Córsico, Alejandro Hugo; Montgomery, Michael Houston (2008) [Artigo de periódico]
      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 ...

    • The pulsations of PG 1351+489 

      Redaelli, Maurício; Kepler, Souza Oliveira; Costa, Jose Eduardo da Silveira; Winget, Donald Earl; Handler, Gerald; Castanheira, Bárbara Garcia; Kanaan Neto, Antonio Nemer; Fraga, Luciano; Henrique, P.; Giovannini Junior, Odilon; Provencal, Judith L.; Shipman, Harry L.; Dalessio, J.; Thompson, S. E.; Mullally, Fergal; Brewer, M. M.; Childers, D.; Oksala, M. E.; Rosen, Rachel; Wood, Matthew A.; Reed, M. D.; Walter, B.; Strickland, Willie; Chandler, Dean W.; Watson, Todd K.; Nather, R. Edward; Montgomery, Michael Houston; Bischoff-Kim, Agnès; Hansen, Carl J.; Nitta, Atsuko; Kleinman, Scot James; Claver, C.F.; Brown, Tim; Sullivan, Denis J.; Kim, Seung-Lee; Chen, Wen-Ping; Yang, M.; Shih, Chia-You; Zhang, X; Jiang, Xiaojun; Fu, Jianning Ning; Seetha, S.; Ashoka, B.N.; Marar, T.M. Krishnan; Baliyan, Kiran S.; Vats, Hari Om; Chernyshev, A.V.; Ibbetson, Peter A.; Leibowitz, Elia M.; Hemar, Shirley; Sergeev, A.; Andreev, M.; Janulis, Rimvydas; Meistas, Edmundas G.; Moskalik, Pawel; Pajdosz, Gabriel; Baran, Andrzej; Winiarski, M.; Zola, Staszek; Ogloza, Waldemar; Siwak, Michal; Bognár, Zsófia; Solheim, Jan-Eric; Sefako, R.; Buckley, David A.H.; O'Donoghue, Darragh; Nagel, Thorsten; Silvotti, Roberto; Bruni, I.; Fremy, J. R.; Vauclair, Gérard; Chevreton, Michel; Dolez, Noël; Pfeiffer, Ben; Barstow, Martin A.; Creevey, o; Kawaler, Steven D.; Clemens, J. Christopher (2011) [Artigo de periódico]
      PG 1351+489 is one of the 20DBVs – pulsating helium-atmospherewhite dwarf stars – known and has the simplest power spectrum for this class of star, making it a good candidate to study cooling rates. We report accurate ...

    • The unusual helium variable AM Canum Venaticorum 

      Provencal, Judith L.; Winget, Donald Earl; Nather, R. Edward; Robinson, E.L.; Solheim, Jan-Eric; Clemens, J. Christopher; Bradley, Paul A.; Kleinman, Scot James; Kanaan Neto, Antonio Nemer; Claver, C.F.; Hansen, Carl J.; Marar, T.M. Krishnan; Seetha, S.; Ashoka, B.N.; Leibowitz, Elia M.; Meistas, Edmundas G.; Bruvold, A.; Vauclair, Gérard; Dolez, Noël; Chevreton, Michel; Barstow, Martin A.; Sansom, A.E.; Tweedy, R.W.; Fontaine, Gilles; Bergeron, Pierre; Kepler, Souza Oliveira; Wood, Matthew A.; Grauer, Albert D. (1995) [Artigo de periódico]
      The unusual variable star AM CVn has puzzled astronomers for over 40 years. This object, both a photometric and spectroscopic variable, is believed to contain a pair of hydrogen-deficient white dwarfs of extreme mass ratio, ...

    • Understanding the cool DA white dwarf pulsator G29-38 

      Kleinman, Scot James; Nather, R. Edward; Winget, Donald Earl; Clemens, J. Christopher; Bradley, Paul A.; Kanaan Neto, Antonio Nemer; Provencal, Judith L.; Claver, C.F.; Watson, Todd K.; Yanagida, K.; Nitta, Atsuko; Dixson, James S.; Wood, Matthew A.; Grauer, Albert D.; Hine, B.P.; Fontaine, Gilles; Liebert, James; Sullivan, Denis J.; Wickramasinghe, D.T.; Achilleos, Nicholas; Marar, T.M. Krishnan; Seetha, S.; Ashoka, B.N.; Meistas, Edmundas G.; Leibowitz, Elia M.; Moskalik, Pawel; Krzesinski, Jerzy; Solheim, Jan-Eric; Bruvold, A.; O'Donoghue, Darragh; Kurtz, Donald W.; Warner, B.; Martinez, Peter; Vauclair, Gérard; Dolez, Noël; Chevreton, Michel; Barstow, Martin A.; Kepler, Souza Oliveira; Giovannini Junior, Odilon; Augusteijn, T.; Hansen, Carl J.; Kawaler, Steven D. (1998) [Artigo de periódico]
      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 ...

    • Whole Earth Telescope observations and seismological analysis of the pre-white dwarf pg 2131+066 

      Kawaler, Steven D.; O'Brien, M. Sean; Clemens, J. Christopher; Nather, R. Edward; Winget, Donald Earl; Watson, Todd K.; Yanagida, K.; Dixson, James S.; Bradley, Paul A.; Wood, Matthew A.; Sullivan, Denis J.; Kleinman, Scot James; Meistas, Edmundas G.; Leibowitz, Elia M.; Moskalik, Pawel; Zola, Staszek; Pajdosz, Y.; Krzesinski, Jerzy; Solheim, Jan-Eric; Bruvold, A.; O'Donoghue, Darragh; Katz, M.; Vauclair, Gérard; Dolez, Noël; Chevreton, Michel; Barstow, Martin A.; Kanaan Neto, Antonio Nemer; Kepler, Souza Oliveira; Giovannini Junior, Odilon; Provencal, Judith L.; Hansen, Carl J. (1995) [Artigo de periódico]
      As transition objects between the asymptotic giant branch (AGB) and cooling white dwarfs, the PG 1159 stars are key objects for understanding the late stages of stellar evolution. The pulsations exhibited by many members ...