Visualisations
The formation of (supermassive-)stars in a galaxy at the beginning of time
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In the two movies above I show the formation of stars in a galaxy at z ~ 16. The galaxy has a virial temperature of approximately 10,000 K immediately prior to star formation and did not form stars prior to this point due to dynamical heating from minor mergers which prevented the galaxy from cooling before reaching the atomic cooling limit. The movie on the left shows the a projection of the density while the movie on the right shows the same region with the colour bar in this case measuring temperature. Stars, which form, are coloured by their type. Blue stars are population III stars, red stars are super-massive stars. The orange star represents the most massive star at that time. The legend in both figures tracks the mass and age of the top 5 most massive stars in the simulation at each time. The simulation stops 2 million years after the formation of the first star at which point supernova will begin to disrupt the galaxy. The most massive star at the end of the simulation has a mass of more than 6000 solar masses making it an ideal candidate for an intermediate mass black hole.
Lyman Werner Radiation and its impact on the gas distribution
This movie shows the impact that radiation in the Lyman-Werner band has on the gas distribution. Molecular hydrogen is dissociated by photons with energies just short of the Hydrogen ionisation threshold. LW radiation is at 12.8 eV and efficiently dissociates H2. Hydrogen (right panel) is not effected by radiation in this waveband.
This movie shows the impact that radiation in the Lyman-Werner band has on the gas distribution. Molecular hydrogen is dissociated by photons with energies just short of the Hydrogen ionisation threshold. LW radiation is at 12.8 eV and efficiently dissociates H2. Hydrogen (right panel) is not effected by radiation in this waveband.
Multi-Frequency Radiation
Radiation in the range 0.7 eV -> 1000 eV.
The effect of the multi-frequency radiation is different for different species.
Another H2 Dissociation Movie
This visualisation shows the H2 fraction in the left panel and the HI (neutral hydrogen) fraction in the right hand panel. The source (white circle) immediately starts to dissociate the H2 as it emits radiation in the Lyman-Werner (LW) band at 12.8 eV. The HI fraction is effectively unchanged as the LW radiation does not ionise HI nor is its fraction changed appreciably due to H2 dissociation.
H2 Dissociation Movie - II
Similar to the first movie above this visualisation shows the H2 fraction in the left panel and the HI (neutral hydrogen) fraction in the right hand panel. This is a zoomed in visualisation run over a much longer time period. The H2 is initially dissociated to quiet a low level but self-shielding in the very centre causes the fraction there to remain at the level of approximately 1×10-6. As the HI density increases as the collapse gains momentum this in turn is able to drive the H2 fraction upwards and this is clearly seen at the end of the visualisation.
Temperature Density Movie
This movie is a projection looking down along the angular momentum vector. The projection width is approximately 1000 AU. The left panel shows the temperature fluctuations as the central object collapses (note the linear temperature scale). The right panel shows the density fluctuations over the exact same timeline. The fragmentation and formation of clumps is clearly visible.
This movie is a projection looking down along the angular momentum vector. The projection width is approximately 1000 AU. The left panel shows the temperature fluctuations as the central object collapses (note the linear temperature scale). The right panel shows the density fluctuations over the exact same timeline. The fragmentation and formation of clumps is clearly visible.
Zoom and look at the temperature and density evolution.
This next movie is similar to the above movie except that it combines a "zoom-in" and time evolution. The scale is given in the bottom left corner and the time in the top right of the left panel. The density scale initially varies strongly before remaining fixed to track the end of the evolution. Notice the incredible dynamic range of Enzo.
This next movie is similar to the above movie except that it combines a "zoom-in" and time evolution. The scale is given in the bottom left corner and the time in the top right of the left panel. The density scale initially varies strongly before remaining fixed to track the end of the evolution. Notice the incredible dynamic range of Enzo.
Gas density rendered in projection. A zoom and rotate.
Rotating Filaments
A view of filament like structures. The gas density is rendering and rotated.
A view of filament like structures. The gas density is rendering and rotated.