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Planetary Nebula Library: Hydro Runs

Update 10/2: Please note that the layout has been changed. Relevant older models have been updated with the new color bars and ranges. The new models are being added and examined for significant differences when compared to existing models.

Go ​here to find a list of changes that were made today.

Reason for Library

Here we explore a variety of possible parameters and environments that can shape planetary nebulae, presented in various forms. This library will record a number of combinations of different density backgrounds and types of flows and also any parameter changes within those different combinations. The environments and flow structures are listed below.

Environments:

• Constant Ambient: The surrounding density is initially constant.
• Stratified Ambient: The surrounding density falls off as 1/r².
• Toroidal Ambient: The surrounding density decays from the equator to the pole as defined in ​Frank & Mellema, 1994 Apj by the following variables:
  • \alpha_{t} describes the contrast in density of the torus from the pole to the equator.
  • \beta_{t} describes how elliptical or spherical the torus is. Small values coincide with a more elliptical torus while values closer to 1 indicate a more spherical torus.

Flow Structures:

• Clump: A spherical cloud of gas.
• Jet: A constant stream of gas.
• Diverging Wind: A constant stream of gas that sweeps an arc in the surrounding medium.

Below are the standard parameters used in each run. Any changes to these parameters will be noted in the table preceding the image table.

Standard Parameters
Jet Radius	500 AU
Jet Density	40,000 cm-3
Jet Temperature	10 K
Ambient Density	400 cm-3
Ambient Temperature	1 K
Torus Alpha (\alpha_{t})	.7
Torus Beta (\beta_{t})	.8

(See ​Ruka's PN Page for MHD models.)

Toroidal + Stratified Ambient

Jet

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Jet Velocity = 100 km/s	Jet Velocity = 200 km/s	Jet Velocity = 300 km/s	Velocity Comparison
​movie	​movie	​movie
​movie	​movie	​movie

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Changes to Standard Parameters
Jet Temperature	10,000 K

Jet Velocity = 100 km/s	Jet Velocity = 200 km/s	Jet Velocity = 300 km/s	Jet Velocity = 500 km/s	Velocity Comparison
​movie	​movie	​movie	*Note time difference!*
​movie	​movie	​movie

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Changes to Standard Parameters
Jet Temperature	10,000 K
Ambient Density	1,000 cm-3

Jet Velocity = 300 km/s

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Changes to Standard Parameters
Ambient Temperature	100 K

Jet Velocity = 100 km/s
*No significant difference between this model and the 100 km/s jet in an ambient with T = 10K*

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Clump

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Clump Velocity = 100 km/s	Clump Velocity = 200 km/s	Clump Velocity = 300 km/s	Velocity Comparison
​movie	​movie	​movie
​movie	​movie	​movie

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Constant Ambient

Jet

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Changes to Standard Parameters
Ambient Density	1 cm-3

Jet Velocity = 100 km/s	Jet Velocity = 200 km/s	Jet Velocity = 300 km/s	Velocity Comparison