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Highly supersonic motions within the outer features of the Eta Carinae nebulosity

J. Meaburn·P. Boumis·J. R. Walsh·W. Steffen·A. J. Holloway·R. J. R Williams·M. Bryce
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Abstract

Spatially resolved H$α$ and [N{\sc ii}] line profiles have been obtained over striking features in the outer regions of the Eta Carinae nebula. The highly irregular outer `shell' of low ionization, [N{\sc ii}] bright, knots has been shown to exhibit radial velocities between -1200 and +300 km/s with respect to the systemic radial velocity, over its perimeter. Furthermore, several knots have been found which appear to emit only in the H$α$ line with radial velocities up to -1450 km/s. However, the most intriguing features are a narrow `spike' that projects through this outer shell and a faint `arc' of emission that extends well beyond it. The `spike', which exhibits a change of radial velocity along its length, could be a narrow collimated jet with an outflow velocity of > 1000 km/s. In one interpretation the `arc' is modelled by a conical outflow and mechanisms for generating [N{\sc ii}] emission from highly supersonic gas are also discussed.

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J. Meaburn, P. Boumis, J. R. Walsh, W. Steffen, A. J. Holloway, R. J. R Williams, M. Bryce. 1996-06-14. Highly supersonic motions within the outer features of the Eta Carinae nebulosity. https://doi.org/10.1093/mnras%2F282.4.1313

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