Seismology of a massive pulsating hydrogen atmosphere white dwarf

• Autor(a) principal: Kepler, Souza Oliveira
• Data de Publicação: 2012
• Outros Autores: 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
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UFRGS
• Texto Completo: http://hdl.handle.net/10183/109055
• topic: Anãs brancas; Atmosferas estelares; Fotometria estelar; Pulsacoes estelares; Espectros estelares; Estrelas variaveis; Séries temporais; Stars: fundamental parameters; Stars: oscillations; White dwarfs

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 pulsations in ZZ Ceti stars. This, along with estimates for the star’s temperature and gravity, establishes it as a massive ZZ Ceti star. We used time-series photometric observations with the 4.1 m SOAR Telescope, complemented by contemporary McDonald Observatory 2.1 m data, to discover the photometric variability. The light curve of SDSS J132350.28+010304.22 shows at least nine detectable frequencies. We used these frequencies to make an asteroseismic determination of the total mass and effective temperature of the star: M★ = 0.88±0.02Mʘ and Teff = 12,100±140 K. These values are consistent with those derived from the optical spectra and photometric colors.