Navegação Ciências Exatas e da Terra por Autor "Córsico, Alejandro Hugo"

Resultados 21-31 de 31

    • Pulsating hydrogen-deficient white dwarfs and pre-white dwarfs observed with TESS : IV. Discovery of two new GW Vir stars : TIC 0403800675 and TIC 1989122424 

      Uzundag, Murat; Córsico, Alejandro Hugo; Kepler, Souza Oliveira; Althaus, Leandro Gabriel; Werner, Klaus; Reindl, Nicole; Vuckovic, Maja (2022) [Artigo de periódico]
      We present two new GW Vir-type pulsating white dwarf stars, TIC 0403800675 (WD J115727.68-280349.64) and TIC 1989122424 (WD J211738.38-552801.18) discovered in the Transiting Exoplanet Survey Satellite (TESS) photometric ...

    • Pulsating low-mass white dwarfs in the frame of new evolutionary sequences : III. The pre-ELM white dwarf instability strip 

      Córsico, Alejandro Hugo; Althaus, Leandro Gabriel; Serenelli, Aldo M.; Kepler, Souza Oliveira; Jeffery, C. Simon; Corti, Mariela Alejandra (2016) [Artigo de periódico]
      Context. Many low-mass (M /M <∼ 0.45) and extremely low-mass (ELM, M /M <∼ 0.18−0.20) white-dwarf stars are currently being found in the field of the Milky Way. Some of these stars exhibit long-period gravity-mode (g-mode) ...

    • Pulsating low-mass white dwarfs in the frame of new evolutionary sequences : VI. Thin H-envelope sequences and asteroseismology of ELMV stars revisited 

      Calcaferro, Leila Magdalena; Córsico, Alejandro Hugo; Althaus, Leandro Gabriel; Romero, Alejandra Daniela; Kepler, Souza Oliveira (2018) [Artigo de periódico]
      Context. Some low-mass white-dwarf (WD) stars with H atmospheres currently being detected in our galaxy, show long-period g(gravity)-mode pulsations, and comprise the class of pulsating WDs called extremely low-mass variable ...

    • Revealing the pulsational properties of the V777 Herculis star KUV 05134+2605 by its long-term monitoring 

      Bognár, Zsófia; Paparo, Margit; Córsico, Alejandro Hugo; Kepler, Souza Oliveira; Györffy, Á. (2014) [Artigo de periódico]
      Context. KUV 05134+2605 is one of the 21 pulsating DB white dwarfs (V777 Her or DBV variables) known so far. The detailed investigation of the short-period and low-amplitude pulsations of these relatively faint targets ...

    • SDSS DR7 white dwarf catalog 

      Kleinman, Scot James; Kepler, Souza Oliveira; Koester, Detlev; Pelisoli, Ingrid Domingos; Antonio, Viviane Peçanha; Nitta, Atsuko; Costa, Jose Eduardo da Silveira; Krzesinski, Jerzy; Dufour, Patrick; Lachapelle, François-René; Bergeron, Pierre; Yip, Ching-Wa; Harris, Hugh C.; Eisenstein, Daniel, J.; Althaus, Leandro Gabriel; Córsico, Alejandro Hugo (2013) [Artigo de periódico]
      We present a new catalog of spectroscopically confirmed white dwarf stars from the Sloan Digital Sky Survey (SDSS) Data Release 7 spectroscopic catalog. We find 20,407 white dwarf spectra, representing 19,712 stars, and ...

    • Seismology of a massive pulsating hydrogen atmosphere white dwarf 

      Kepler, Souza Oliveira; Pelisoli, Ingrid Domingos; Antonio, Viviane Peçanha; Costa, Jose Eduardo da Silveira; Fraga, Luciano; Hermes, James J.; Winget, Donald Earl; Castanheira, Bárbara Garcia; Córsico, Alejandro Hugo; Romero, Alejandra Daniela; Althaus, Leandro Gabriel; Kleinman, Scot James; Nitta, Atsuko (2012) [Artigo de periódico]
      We report our observations of the new pulsating hydrogen atmosphere white dwarf SDSS J132350.28+010304.22. We discovered periodic photometric variations in frequency and amplitude that are commensurate with nonradial g-mode ...

    • 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 rate of cooling of the pulsating white dwarf star G117−B15A : a new asteroseismological inference of the axion mass 

      Córsico, Alejandro Hugo; Althaus, Leandro Gabriel; Bertolami, Marcelo Miguel Miller; Romero, Alejandra Daniela; García-Berro, Enrique; Isern, J.; Kepler, Souza Oliveira (2012) [Artigo de periódico]

    • The white dwarf mass–radius relation and its dependence on the hydrogen envelope 

      Romero, Alejandra Daniela; Kepler, Souza Oliveira; Joyce, Simon R. G.; Ramos, Gabriel Lauffer; Córsico, Alejandro Hugo (2019) [Artigo de periódico]
      We present a study of the dependence of the mass–radius relation for DA white dwarf stars on the hydrogen envelope mass and the impact on the value of log g, and thus the determination of the stellar mass. We employ a set ...

    • Toward ensemble asteroseismology of ZZ Ceti stars with fully evolutionary models 

      Romero, Alejandra Daniela; Córsico, Alejandro Hugo; Althaus, Leandro Gabriel; Kepler, Souza Oliveira; Castanheira, Bárbara Garcia; Bertolami, Marcelo Miguel Miller (2012) [Artigo de periódico]
      ZZ Ceti stars form the most numerous group of degenerate variable stars. They are otherwise normal DA (H-rich atmospheres) white dwarfs that exhibit pulsations. Here, we present an asteroseismological analysis for 44 bright ...

    • Two new pulsating low-mass pre-white dwarfs or SX Phoenicis stars? 

      Corti, Mariela Alejandra; Kanaan Neto, Antonio Nemer; Córsico, Alejandro Hugo; Kepler, Souza Oliveira; Althaus, Leandro Gabriel; Koester, Detlev; Sánchez Arias, J. P. (2016) [Artigo de periódico]
      Context. The discovery of pulsations in low-mass stars opens an opportunity to probe their interiors and determine their evolution by employing the tools of asteroseismology. Aims. We aim to analyse high-speed photometry ...