Seismology of a massive pulsating hydrogen atmosphere white dwarf

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 tempe...

Descripción completa

Detalles Bibliográficos
Autores: 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
Tipo de documento: Artículo
Estado:Published version
Fecha de publicación:2012
País:Brasil
Institución:UFRGS
Repositorio:Repositório Institucional da UFRGS
Lenguaje:Inglés
OAI Identifier:oai:www.lume.ufrgs.br:10183/109055
Acceso en línea:http://hdl.handle.net/10183/109055
Nivel de acceso:Acceso abierto
Palabra clave:Anãs brancas
Atmosferas estelares
Fotometria estelar
Pulsacoes estelares
Espectros estelares
Estrelas variaveis
Séries temporais
Stars: fundamental parameters
Stars: oscillations
White dwarfs
Descripción
Sumario: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.