Particle distribution method for the homologous collapse of a sphere
Abstract
In this work the adiabatic collapse of a sphere is studied. self-gravitating through a computational simulation
carried out with Gadget-2. This package has a simulation archetype for the homologous collapse of a unit
sphere, which is represented by a series of concentric spherical shells, where the particles are equidistantly
distributed to represent a density ρ ~ r2. Another method has been created based on considering the unit
sphere made up of small spheres inside. The problem comes down to packing the small spheres in the best
possible way. This problem has been solved in solid state physics. For spherical symmetry, the maximum
packing factor is given by an FCC-type Bravais structure. In this work it is shown that the Gadget archetype
is equivalent to a CS structure that has a smaller packing factor. Consequently, the best way to represent a
gas sphere computationally is by means of an FCC distribution.
Keywords
Homologous collapse, Molecular cloud, Gadget-2
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