Navegação por Assunto "Nebulosas planetarias"

Resultados 1-8 de 8

    • 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 ...

    • Discovery of an open cluster with a possible physical association with a planetary nebula 

      Bonatto, Charles Jose; Bica, Eduardo Luiz Damiani; Santos Junior, Joao Francisco Coelho dos (2008) [Artigo de periódico]
      We report the discovery of a new open cluster (OC) in the Galaxy at l = 167◦ 0 and b = −1◦ 0. Its field includes the planetary nebula (PN) PK 167−0.1. We study the possible associations of the PN/OC pairs NGC2818/2818A, ...

    • Investigating potential planetary nebula/cluster pairs 

      Moni Bidin, Christian; Majaess, Daniel J.; Bonatto, Charles Jose; Mauro, Francesco; Turner, D. G.; Geisler, Doug; Chené, André-Nicolas; Gormaz-Matamala, Alex C.; Borissova, Jura; Kurtev, Radostin Georgiev; Minniti, Dante; Carraro, Giovanni; Gieren, Wolfgang P. (2014) [Artigo de periódico]
      Context. Fundamental parameters characterizing the end-state of intermediate-mass stars may be constrained by discovering planetary nebulae (PNe) in open clusters (OCs). Cluster membership may be exploited to establish the ...

    • Molecular chemistry and the missing mass problem in planetary nebulae 

      Kimura, Rafael Kobata; Gruenwald, Ruth B.; Aleman, Isabel Regina Guerra (2012) [Artigo de periódico]
      Context. Detections of molecular lines, mainly from H₂ and CO, reveal molecular material in planetary nebulae. Observations of a variety of molecules suggest that the molecular composition in these objects differs from ...

    • On the possible existence of short-period g-mode instabilities powered by nuclear-burning shells in post-asymptotic giant branch h-deficient (PG1159-TYPE) stars 

      Córsico, Alejandro Hugo; Althaus, Leandro Gabriel; Bertolami, Marcelo Miguel Miller; Gonzalez Perez, Jose Miguel; Kepler, Souza Oliveira (2009) [Artigo de periódico]
      We present a pulsational stability analysis of hot post-asymptotic giant branch (AGB) H-deficient pre-white dwarf stars with active He-burning shells. The stellar models employed are state-of-the-art equilibrium structures ...

    • Planetary nebulae and the ionization of the interstellar medium in galaxies 

      Stasinska, Grazyna; Trevisan, Marina; Asari, Natalia Vale (2022) [Artigo de periódico]
      We discuss the role of planetary nebulae and their progeny in galaxy context in terms of ionization of the galaxy interstellar medium. This regards ionized gas outside the disk of spiral galaxies, the diffuse ionized medium ...

    • A study of the neglected Galactic HII region NGC 2579 and its companion ESO 370-9 

      Copetti, Marcus Vinicius Fontana; Oliveira, Vinicius de A.; Riffel, Rogério; Castañeda, Héctor O.; Sanmartim, D. (2007) [Artigo de periódico]
      Context. The Galactic Hii region NGC 2579 has stayed undeservedly unexplored due to identification problems which persisted until recently. Both NGC 2579 and its companion ESO 370-9 have been misclassified as planetary or ...

    • Three globular cluster candidates in the direction of the bulge shown to be small emission nebulae 

      Bica, Eduardo Luiz Damiani; Claria Olmedo, Juan Jose; Bonatto, Charles Jose; Piatti, Andres E.; Ortolani, Sergio; Barbuy, Beatriz (1995) [Artigo de periódico]
      We carried out spectrophotometry in the range 4000- 7000Å and V, I and Gunn z imaging of the initially thought to be globular cluster candidates in the direction of the Galactic bulge TJ 5 and TJ 23 (Terzan & Ju 1980) and ...