CHOLLA test: spherical collapse

Spherical Collapse:

Black ring shows the size of the spherical overdensity size for a pressure-less collapse.

The initial conditions are \(\rho=1\) for the overdensity, \(\rho=1e^{-4}\) for the background, uniform pressure \(p=5e^{-3}\).

Simulation is adiabatic and uses VL integrator.