This code uses the algorithm found in Radionov, Athanassoula & Sotnikova (2009) for generating the initial conditions for a galaxy simulation with the code GADGET-2, including live gaseous/stellar disk, halo and bulge components.

To use it, you need to compile 4 different modified versions of GADGET-2 and put them in the galaxy/ folder, with the names gadget_0, gadget_1, gadget_2 and gadget_3. They respectively only allow gas particles, dark matter particles, disk particles and bulge particles to move. I manually updated GADGET-2 for that. Additionally, gadget_0 must be compiled with the -DISOTHERMAL flag.

This code is highly experimental, and I don't use it anymore for three reasons: it takes a long time to generate the initial conditions; it has an unidentified bug which makes halo and bulge particles accumulate around the z axis once the galaxy is simulated; and I have another code that just works™, which is available in the galstep repository.

• NumPy (python-numpy)
• SciPy (python-scipy)
• pyGadgetReader

usage: galaxy.py [-h] [-o init.dat] [-cores CORES]

optional arguments:
  -h, --help    show this help message and exit
  -o init.dat   The name of the output file.
  -cores CORES  The number of cores to use.

Feel free to use this code in your work, but please link this page in your paper.