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A 3-mode, Variable Velocity Jet Model for HH 34

A. Raga·A. Noriega-Crespo
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Abstract

Variable ejection velocity jet models can qualitatively explain the appearance of successive working surfaces in Herbig-Haro (HH) jets. This paper presents an attempt to explore which features of the HH-34 jet can indeed be reproduced by such a model. From previously published data on this object, we find evidence for the existence of a 3-mode ejection velocity variability, and then explore the implications of such a variability. From simple, analytic considerations it is possible to show that the longer period modes produce a modulation on the shorter period modes, resulting in the formation of ``trains'' of multiple knots. The knots observed close to the source of HH-34 could correspond to such a structure. Finally, a numerical simulation with the ejection velocity variability deduced from the HH-34 data is computed. This numerical simulation shows a quite remarkable resemblance with the observed properties of the HH-34 jet.

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A. Raga, A. Noriega-Crespo. 1998-08-25. A 3-mode, Variable Velocity Jet Model for HH 34. https://doi.org/10.1086/300641

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