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arXiv · 2402.11850

The Molecular Exoskeleton of the Ring-like Planetary Nebula NGC 3132

Joel H. Kastner·David Wilner·Paula Moraga Baez·Jesse Bublitz·Orsola De Marco·Raghvendra Sahai·Al Wootten
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Abstract

We present Submillimeter Array (SMA) mapping of $^{12}$CO $J=2\rightarrow 1$, $^{13}$CO $J=2\rightarrow 1$, and CN $N=2\rightarrow 1$ emission from the Ring-like planetary nebula (PN) NGC 3132, one of the subjects of JWST Early Release Observation (ERO) near-infrared imaging. The $\sim$5$''$ resolution SMA data demonstrate that the Southern Ring's main, bright, molecule-rich ring is indeed an expanding ring, as opposed to a limb-brightened shell, in terms of its intrinsic (physical) structure. This suggests that NGC 3132 is a bipolar nebula viewed more or less pole-on (inclination $\sim$15--30$^\circ$). The SMA data furthermore reveal that the nebula harbors a second expanding molecular ring that is aligned almost orthogonally to the main, bright molecular ring. We propose that this two-ring structure is the remnant of an ellipsoidal molecular envelope of ejecta that terminated the progenitor star's asymptotic giant branch evolution and was subsequently disrupted by a series of misaligned fast, collimated outflows or jets resulting from interactions between the progenitor and one or more companions.

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Joel H. Kastner, David Wilner, Paula Moraga Baez, Jesse Bublitz, Orsola De Marco, Raghvendra Sahai, Al Wootten. 2024-02-19. The Molecular Exoskeleton of the Ring-like Planetary Nebula NGC 3132. https://arxiv.org/abs/2402.11850

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