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Name

mknbody5 - Create initial conditions using the NBODY5 program

Synopsis

mknbody5 [parameter=value]

Description

mknbody5 is a NEMO frontend to Aarseth’s nbody5(1NEMO) program with which you can create initial conditions. This is done by creating an input parameter file for nbody5, which sets up the initial conditions but doesn’t integrate (TCRIT=0.0). The nbody5 output file is then converted to standard snapshot(5NEMO) format using u3tos(1NEMO) .

Parameters

The following parameters are recognized in any order if the keyword is also given:
out=
Output snapshot(5NEMO) file. No default.
nbody=
Number of bodies. [Default: t].
seed=
Random number seed. 0 takes a random number from the time of the day. [Default: 0].
nbin=
Number of initial binaries. [Default: 0].
rbar=
Virial radius in pc (for scaling) [Default: 1.0].
zmbar=
Mean mass in solar mass (for scaling) [Default: 6.0].
mass0=
Lower mass cutoff [Default: 1.0].
mass1=
Upper mass cutoff [Default: 6.0].
alpha=
Power law index for Initial Mass Function (as defined by N(m) = m**(-alpha)). [Default: 2.5].
imf=
Choice of IMF (Valid options are: scalo, kroupa, eggleton). [Default: scalo].
virial=
Initial virial (1=equilibrium) [Default: t].
vxrot=
XY-velocity scaling factor (>0 for solid body) [Default: t].
vzrot=
Z-velocity scaling factor (not used of vxrot=0) [Default: t].
run=t|f
Run nbody5 and convert the data to snapshot format? Note: if you choose to use this option any existing file OUT3 will be removed prior to running body5.
save=t|f
COMMON save on unit 1? This may be useful if you want to restart a similation (KSTART>1) from these initial conditions with different paramters. It is (I believe) not possible (as in NBODY1/2 ??) to read initial conditions from a file compatible with UNIT 3. [Default: f].

Caveats

Not all features have been implemented, in particular features that cannot be exported through a simple mass and phase-space format snapshot-like output format (e.g. mass loss, molecular clouds, external force field etc.)

Since some file names (see FILES below) are fixed, it is dangerous to run this program in parallel.

The out= output file does not contain the full history, i.e. input paramaters of this program.

Small number of particles (nbody=) will not work properly yet. Some paramters need to scale with N for small N.

Examples

See Also

nbody5(1) , u3tos(1NEMO)

Files


OUT3        NBODY5 binary snapshot (see also u3tos(1NEMO))
nbody5.in   input parameter file
AuthorPeter Teuben Update History
10-jun-95    V0.1 Created a basic version    PJT


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