Planet(s) configuration file


A planetary system config file has a content similar to the following. The extension for
this file is usually '.cfg', but it can be any extension. It is called at runtime by the use of the
parameter PlanetConfig.

###########################################################
#
#   Planetary system initial configuration
#
# Note: Accretion is the inverse of the accretion
#       time scale (1.0 for Kley's standard set-up)
#       Set to 0 to turn accretion off
###########################################################

# Planet Name     Distance    Mass     Accretion    Feels Disk    Feels Others
Jupiter            1.0        0.002     0.0         YES           YES
Saturn             2.0        0.00029   1.0         YES           YES

Any blank line or line begining this a # is ignored.
A line containing a planet description contains the following information (the separators between the different fields can be an arbitray number, or combination, of tabulations and spaces):

  1. The first field is the planet name. It must begin with a character ('a' to 'z' or 'A' to 'Z'). 'Jupiter4' is a valid planet name, '15earthmass' is not : this planet will not be recognised.
  2. The second field is the planet orbital radius a. Note that the planet at t=0 will have x=a, y=0, vy>0 and vx=0 (unless you give it some eccentricity).
  3. The third field is the planet to primary mass ratio. Note that the primary is assumed to have mass 1.
  4. The fourth parameter sets the accretion properties within the Roche lobe. It is the inverse of the accretion timescale, therefore setting this parameter to 0 inhibits accretion. For further details about the accretion procedure, see Kley (1999) or have a look at the AccreteOntoPlanets function in src/Planet.c
  5. The fifth parameter has to be either 'YES' or 'NO'. It indicates whether the planet "feels" the disk tidal field or not. If you want the planet to remain on a fixed circular orbit, set this field to 'NO'. Setting it to 'YES' will allow it to migrate.
  6. Finally, the sixth and last parameter indicates whether this planet feels the potential of the other planets possibly present in the system. You have to set it to 'YES' if you want for instance to get mean motion resonances between your planets. Note that a planet will always feel the primary potential.