ABSTRACT Current models predict that binary interactions are a major ingredient in the formation of bipolar planetary nebulae (PNe) and pre-planetary nebulae (PPNe). Despite years of radial velocity (RV) monitoring, the paucity of known binaries amongst the latter systems means data are insufficient to examine this relationship in detail. In this work, we report on the discovery of a long-period (P = 2654 ± 124 d) binary at the centre of the Galactic bipolar PPN IRAS 08005−2356 (V510 Pup), determined from long-term spectroscopic and near-infrared time-series data. The spectroscopic orbit is fitted with an eccentricity of 0.36 ± 0.05, which is similar to that of other long-period post-AGB binaries. Time-resolved Hα profiles reveal high-velocity outflows (jets) with deprojected velocities up to 231$_{-27}^{+31}$ km s−1 seen at phases when the luminous primary is behind the jet. The outflow traced by Hα is likely produced via accretion on to a main-sequence companion, for which we calculate a mass of 0.63 ± 0.13 M⊙. This discovery is one of the first cases of a confirmed binary PPN and demonstrates the importance of high-resolution spectroscopic monitoring surveys using large telescopes in revealing binarity among these systems.
Common-envelope shaping of planetary nebulae – IV. From protoplanetary to planetary nebula
We present 2D hydrodynamical simulations of the transition of a protoplanetary nebula (PPN) to a planetary nebula for central stars in binary systems that have undergone a common-envelope event. After 1000 yr of magnetically driven dynamics (PPN phase), a line-driven stellar wind is introduced into the computational domain and the expansion of the nebula is simulated for another 10 000 yr, including the effects of stellar photoionization. In this study we consider central stars with main sequence (final) masses of 1 (0.569) and 2.5 (0.677) M⊙, together with a 0.6-M⊙ main-sequence companion. Extremely bipolar, narrow-waisted PPNe result in bipolar planetary nebulae, while the rest of the shapes mainly evolve into elliptical planetary nebulae. The initial magnetic field’s effects on the collimated structures, such as jets, tend to disappear in most of the cases, leaving behind the remnants of those features in only a few cases. Equatorial zones fragmented mainly by photoionization (1-M⊙progenitors), result in ‘necklace’ structures made of cometary clumps aligned with the radiation field. On the other hand, fragmentation by photoionization and shocked wind (2.5-M⊙progenitors) give rise to the formation of multiple clumps in the latitudinal direction, which remain within the lobes, close to the center, which are immersed and surrounded more »
- Publication Date:
- NSF-PAR ID:
- 10377632
- Journal Name:
- Monthly Notices of the Royal Astronomical Society
- Volume:
- 517
- Issue:
- 3
- Page Range or eLocation-ID:
- p. 3822-3831
- ISSN:
- 0035-8711
- Publisher:
- Oxford University Press
- Sponsoring Org:
- National Science Foundation
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