Importance of the initial conditions for star formation

The initial conditions play an important role in star formation. Both the initial turbulent motions as well as the density configuration determine the fragmentation of the gas as well as the formation of protostars and accretion onto them. The three papers associated with our work are

The video shows the comparison between two density profiles with the same initial turbulent velocity fields. On the density is set up as a scales Bonnor-Ebert sphere, on the right the gas follows a power-law distribution with index -1.5.

other video formats avi (8MB), mov (3.2MB)


Sink particle data

The stars are Lagrangian sink particles that move relative to the grid and are able to accrete gas. For follow-up studies and comparison projects we provide the sink particle data. The files include the following entries for every sink particle and every time step

  • sink particla tag (unique integer identifier)
  • time in the simulation (in seconds)
  • positions in x, y, z (in cm relative to box center)
  • velocities in x, y, z (in cm/s)
  • accelerations in x, y, z (in cm/s^2)
  • angular momentum x, y, z (in g cm^2/s)
  • mass (in g)
  • accretion rate (in g/s)
  • simulation time step (integer time step after the formation of the first sink particle)
  • total number of sinks in this time step
  • total mass in sinks in this time step (in g)
simulationdensity profileturbulenceseeddata file
TH-m-1 top hat mixed 1 bzip2 (40 MB)
TH-m-2 top hat mixed 2 bzip2 (61 MB)
BE-c-1 BE sphere compressive 1 bzip2 (45 MB)
BE-c-2 BE sphere compressive 2 bzip2 (44 MB)
BE-m-1 BE sphere mixed 1 bzip2 (30 MB)
BE-m-2 BE sphere mixed 2 bzip2 (35 MB)
BE-s-1 BE sphere solenoidal 1 bzip2 (26 MB)
BE-s-2 BE sphere solenoidal 2 bzip2 (42 MB)
PL15-c-1 power-law, 1.5 compressive 1 bzip2 (96 MB)
PL15-c-2 power-law, 1.5 compressive 2 bzip2 (125 MB)
PL15-m-1 power-law, 1.5 mixed 1 bzip2 (5 MB)
PL15-m-2 power-law, 1.5 mixed 2 bzip2 (80 MB)
PL15-s-1 power-law, 1.5 solenoidal 1 bzip2 (5 MB)
PL15-s-2 power-law, 1.5 solenoidal 2 bzip2 (145 MB)
PL20-c-1 power-law, 2.0 compressive 1 bzip2 (3 MB)

You can also download all files (bzip2, 782 MB). There is also a small C++ program that helps reading in the files and does a basic sorting of the data (tar, 24kB).