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arXiv · 1512.02330

Discovery of collimated bipolar outflows in the planetary nebula Th 2-A

Ashkbiz Danehkar
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Abstract

We present a comprehensive set of spatially resolved, integral field spectroscopic mapping of the Wolf-Rayet planetary nebula Th 2-A, obtained using the Wide Field Spectrograph on the Australian National University 2.3-m telescope. Velocity-resolved H$α$ channel maps with a resolution of 20 km s$^{-1}$ allow us to identify different kinematic components within the nebula. This information is used to develop a three-dimensional morpho-kinematic model of the nebula using the interactive kinematic modeling tool SHAPE. These results suggest that Th 2-A has a thick toroidal shell with an expansion velocity of 40 $\pm$ 10 km s$^{-1}$, and a thin prolate ellipsoid with collimated bipolar outflows toward its axis reaching velocities in the range of 70-110 km s$^{-1}$, with respect to the central star. The relationship between its morpho-kinematic structure and peculiar [WO]-type stellar characteristics deserves further investigation.

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Ashkbiz Danehkar. 2015-12-08. Discovery of collimated bipolar outflows in the planetary nebula Th 2-A. https://doi.org/10.1088/0004-637x%2F815%2F1%2F35

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