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Initial Conditions

CosmicGrain production ICs use HDF5 format and a seven-type GADGET header. MUSIC2 output must be post-processed before it is passed to a build compiled with NTYPES=7.

Required initial state

  • PartType0: gas in the high-resolution region
  • PartType1: high-resolution dark matter
  • PartType2: coarser dark matter surrounding the zoom
  • PartTypes3–5: empty in the accepted suite
  • PartType6: present but empty

The header arrays NumPart_ThisFile, NumPart_Total, NumPart_Total_HighWord, and MassTable must each contain seven entries. See Particle Types.

Never begin a production run from a MUSIC2 file based only on a successful generator exit code. Run the complete IC-suite validator, then perform a GADGET startup test.

The accepted filename convention is:

ICs/halo<HALO>/IC_halo<HALO>_zoom_<RES>.hdf5

Do not edit accepted HDF5 ICs in place after validation. If post-processing changes, regenerate or create a newly named, newly validated version.