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arXiv · 1203.1297

The filamentary Multi-Polar Planetary Nebula NGC 5189

Abstract

We present a set of optical and infrared images combined with long-slit, medium and high dispersion spectra of the southern planetary nebula (PN) NGC 5189. The complex morphology of this PN is puzzling and has not been studied in detail so far. Our investigation reveals the presence of a new dense and cold infrared torus (alongside the optical one) which probably generated one of the two optically seen bipolar outflows and which might be responsible for the twisted appearance of the optical torus via an interaction process. The high-resolution MES-AAT spectra clearly show the presence of filamentary and knotty structures as well as three expanding bubbles. Our findings therefore suggest that NGC 5189 is a quadrupolar nebula with multiple sets of symmetrical condensations in which the interaction of outflows has determined the complex morphology.

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L. Sabin, R. Vázquez, J. A. López, Ma. T. García-Díaz, G. Ramos-Larios. 2012-03-06. The filamentary Multi-Polar Planetary Nebula NGC 5189. https://arxiv.org/abs/1203.1297

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