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eMail: icke@strw.LeidenUniv.nl

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Planetary Nebula Hydrodynamics:

Movies of Numerical Work

See the printed papers on my PN site, or browse in the electronic issues of Astronomy &Astrophysics. Caution Websurfers: these movies take quite a while to download! They are given in two formats: one low-quality at high compression, and one high quality that has about twice the size of the compressed version. For people with slower line connections, I have included a few movies of low-resolution simulations. All movies are in QuickTime format (Movie JPEG A-compression).

 

Case 3: Conical Burst

In these computations, the inflow from the central star is impulsive: a conical outburst that briefly blasts a supersonic stream into the surrounding nebula. Notice the dramatic difference with the other cases. Although the outer shock of the nebula assumes the familiar bipolar shape (as the analytic calculations say it should), the inner structure is quite different. In particular the temperature shows how a hot ring plume remains and propagates along the axis after the inflow has turned off. Notice the complicated shock waves reverberating in the nebular cavity after the injection has stopped. Some of these are reflected right back towards the central star, where a disk and a spindle of high density are formed. These features are due to the high degree of symmetry of the nebula; if there are deviations from an exact cylindrical shape, things are expected to be different.

Bipolar Nebula Shaped by a Conical Injection

Click to enlarge
 Numerical computation of a brief conical gas stream shooting into a slightly flattened atmosphere. In this composite image, red indicates the density, green the temperature, and blue the velocity of the gas. The image is cylindrically symmetric about the horizontal axis. The dying star, which is now a young white dwarf, is in the centre of the image. You can download a low-quality movie (3.4 Mb) or a high quality movie (6.9 Mb). Both movies are in QuickTime format.

Conical Injection: density

Click to enlarge
 Numerical computation of a brief conical gas stream shooting into a slightly flattened atmosphere. In this movie you see only the density of the gas. Notice how a set of complicated shock waves reverberates in the nebular cavity after the injection has shut off. Red indicates high values, blue/purple is low. The image is cylindrically symmetric about the horizontal axis. You can download a low-quality movie (3.9 Mb) or a high quality movie (8.3 Mb). Both movies are in QuickTime format.

Conical Injection: temperature

Click to enlarge
 Numerical computation of a brief conical gas stream shooting into a slightly flattened atmosphere. In this movie you see only the temperature of the gas. Notice the turbulent hot plume (yellow region) propagating outward after the burst has stopped. This should be observable in X-rays! Red indicates high values, blue/purple is low. The image is cylindrically symmetric about the horizontal axis. You can download a low-quality movie (4.1 Mb) or a high quality movie (8.7 Mb). Both movies are in QuickTime format.

Conical Injection: velocity

Click to enlarge
 Numerical computation of a brief conical gas stream shooting into a slightly flattened atmosphere. In this movie you see only the velocity of the gas. Notice the complicated shock waves reverberating in the nebular cavity after the injection has shut off. Red indicates high values, blue/purple is low. The image is cylindrically symmetric about the horizontal axis. You can download a low-quality movie (5.1 Mb) or a high quality movie (11.6 Mb). Both movies are in QuickTime format.

 

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