Proof of polar ejection from the close-binary core of the planetary nebula Abell 63
Por:
Mitchell D.L., Pollacco D., O'Brien T.J., Bryce M., López J.A., Meaburn J., Vaytet N.M.H.
Publicada:
1 ene 2007
Resumen:
We present the first detailed kinematical analysis of the planetary nebula Abell 63, which is known to contain the eclipsing close-binary nucleus UU Sge. Abell 63 provides an important test case in investigating the role of close-binary central stars on the evolution of planetary nebulae. Longslit observations were obtained using the Manchester echelle spectrometer combined with the 2.1-m San Pedro Martir Telescope. The spectra reveal that the central bright rim of Abell 63 has a tube-like structure. A deep image shows collimated lobes extending from the nebula, which are shown to be high-velocity outflows. The kinematic ages of the nebular rim and the extended lobes are calculated to be 8400 ± 500 and 12900 ± 2800 yr, respectively, which suggests that the lobes were formed at an earlier stage than the nebular rim. This is consistent with expectations that disc-generated jets form immediately after the common envelope phase. A morphological-kinematical model of the central nebula is presented and the best-fitting model is found to have the same inclination as the orbital plane of the central binary system; this is the first proof that a close-binary system directly affects the shaping of its nebula. A Hubble-type flow is well-established in the morphological-kinematical modelling of the observed line profiles and imagery. Two possible formation models for the elongated lobes of Abell 63 are considered, (i) a low-density, pressure-driven jet excavates a cavity in the remnant asymptotic giant branch (AGB) envelope; (ii) high-density bullets form the lobes in a single ballistic ejection event. © 2006 RAS.
Filiaciones:
Mitchell D.L.:
Jodrell Bank Observatory, School of Physics and Astronomy, University of Manchester, Macclesfield SK11 9DL, United Kingdom
Pollacco D.:
Department of Pure and Applied Physics, Queen's University Belfast, Belfast BT7 1NN, United Kingdom
O'Brien T.J.:
Jodrell Bank Observatory, School of Physics and Astronomy, University of Manchester, Macclesfield SK11 9DL, United Kingdom
Bryce M.:
Jodrell Bank Observatory, School of Physics and Astronomy, University of Manchester, Macclesfield SK11 9DL, United Kingdom
López J.A.:
Instituto de Astronomía, Universidad Nacional Autnoma de México, Apartado Postal 877, 22800 Ensenada, B.C., Mexico
Meaburn J.:
Jodrell Bank Observatory, School of Physics and Astronomy, University of Manchester, Macclesfield SK11 9DL, United Kingdom
Vaytet N.M.H.:
Jodrell Bank Observatory, School of Physics and Astronomy, University of Manchester, Macclesfield SK11 9DL, United Kingdom
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