Morpho-kinematic analysis of the point-symmetric, bipolar planetary nebulae Hb 5 and K 3-17, a pathway to poly-polarity

TL;DR

This study uses high-resolution spectra and imaging to analyze the complex 3D structures and kinematics of the bipolar planetary nebulae Hb 5 and K 3-17, revealing their potential evolution into poly-polar nebulae.

Contribution

It provides a detailed 3D kinematic model of Hb 5, showing non-homologous lobe growth and secondary lobes, and suggests a pathway for bipolar nebulae to develop poly-polar features.

Findings

Large lobes grow non-homologously

Secondary lobes emerge from the core

Interaction shapes nebular structure

Abstract

The kinematics of the bipolar planetary nebulae Hb~5 and K 3-17 are investigated in detail by means of a comprehensive set of spatially resolved high spectral resolution, long-slit spectra. Both objects share particularly interesting characteristics, such as a complex filamentary, rosette-type nucleus, axial point-symmetry and very fast bipolar outflows. The kinematic information of Hb~5 is combined with {\it HST} imagery to construct a detailed 3D model of the nebula using the code SHAPE. The model shows that the large scale lobes are growing in a non-homologous way. The filamentary loops in the core are proven to actually be secondary lobes emerging from what appears to be a randomly punctured, dense, gaseous core and the material that forms the point symmetric structure flows within the lobes with a distinct kinematic pattern and its interaction with the lobes has had a shaping effect on them. Hb~5 and K~3-17 may represent a class of fast evolving planetary nebulae that will develop poly-polar characteristics once the nebular core evolves and expands.