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arXiv · 2010.06680

A "head/tail" plasmon model with a Hubble law velocity profile

A. C. Raga·A. Rodriguez-Gonzalez·L. Hernande-Martinez·J. Canto·A. Castellanos-Ramirez
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Abstract

We present a model of a hypersonic, collimated, "single pulse" outflow, produced by an event with an ejection velocity that first grows, reaches a peak, and then decreases again to zero velocity in a finite time (simultaneously, the ejection density can have an arbitrary time-variability). We obtain a flow with a leading "head" and a trailing "tail" that for times greater than the width of the pulse develops a linear, "Hubble law" velocity vs. position. We present an analytic model for a simple pulse with a parabolic ejection velocity vs. time and time-independent mass-loss rate, and compare it to an axisymmetric gasdynamic simulation with parameters appropriate for fast knots in planetary nebulae. This "head/tail plasmon" flow might be applicable to other high-velocity clumps with "Hubble law" tails.

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A. C. Raga, A. Rodriguez-Gonzalez, L. Hernande-Martinez, J. Canto, A. Castellanos-Ramirez. 2020-10-13. A "head/tail" plasmon model with a Hubble law velocity profile. https://doi.org/10.1093/mnrasl%2Fslaa165

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