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arXiv · 1109.4999

Observing Compact Disks Inside Pre-Planetary Nebulae with the Very Large Telescope Interferometer

S. N. Bright·O. De Marco·O. Chesneau·E. Lagadec·H. Van Winckel·B. J. Hrivnak
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Abstract

AGB stars appear to lose mass spherically, but many PNe resulting from the AGB mass-loss have non-spherical morphologies. Compact disks have been found in some bipolar PNe, but their role in the shaping process remains unknown. Compact Keplarian disks are found to be common around post-AGB binaries, however, these objects may never develop into PNe. Another group of post-AGB stars, known as pre-PNe, are surrounded by collimated nebulae shining by reflected light or shock ionisation. We are observing the inner circumstellar regions of pre-PNe at high angular resolutions with the VLTI. We seek to compare pre-PNe disks to those around other post-AGB stars and PNe. New observations of the pre-PN, IRAS 16279-4757, show evidence for a disk similar to those seen in young PNe.

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S. N. Bright, O. De Marco, O. Chesneau, E. Lagadec, H. Van Winckel, B. J. Hrivnak. 2011-09-23. Observing Compact Disks Inside Pre-Planetary Nebulae with the Very Large Telescope Interferometer. https://doi.org/10.1017/s1743921312010800

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