Table of Contents

Name

super, supergp, superst - particle-mesh code with high-resolution subgrids (superbox)

Synopsis

super

Description

superbox is an efficient code for collisionless galactic dynamics. It is an improved particle-mesh code with high resolution sub-grids focused either on the center of mass or center of density of the galaxies. It can treat an arbitrary number of galaxies without requiring extra computational resources. It is a fast and low-storage algorithm that can be used even on small PCs and workstations.

super can contain cosmological. supergp include galactic potential. superst include sticky particles code.

Files


$NEMO/usr/superbox
The main files associated with the run are (notice the basename ’galaxy’ is fixed by the code):
name        small file with the name of the simulation (e.g. modelxy)
modelxy.CONT    input data
modelxy.CONT0    ??
modelxy.CONT1    ??
modelxy.HEAD    output summary of runtime-calculated quantities per timestep
modelxy.DTENS    ??
modelxy.ITENS    ??
modelxy.LOG    logfile
modelxy.adat    ??
modelxy.edat    ??
modelxy.dens    ??
modelxy.potn    ??
modelxy.star    ??
modelxy.out    ??
bla    blabla

Initial conditions is a direct-access file. The first header contains 60 integers (only some are used), followed by 60 reals. After this the data for each star is followed, only the phase space coordinates are needed (x,y,z,vx,vy,vz), in records of 6 reals..

 ih(1)    number of galaxies (gnum)
 ih(2)    total number of stars (istno)
 ....
 fh(1)    size of inner grid (rcore)
 fh(2)    size of middle grid (rout)
 fh(3)    size of local universe (rsystem)
 fh(4)    size of time-step (dt)
 .....
Here are the fortran-style I/O used in the code. Notice the tricky multiple OPEN/CLOSE for the different record lengths:
    integer ih(60)
    real    fh(60), posvel(6)
    open (1,ACCESS=’DIRECT’,RECL=240,IOSTAT=iso)
    write (1,rec = 1) ih 
    write (1,rec = 2) fh 
    close(1)
    open (1,ACCESS=’DIRECT’,RECL=24,IOSTAT=iso)
    do i=1,nstar
       ...
       write(1,rec=20+i) posvel
    end do
    close(1)

Compilation

Note that the maximum grid size and maximum amount of particles are hardcoded during compilation. See comments in rjinclude.h how to change the maximum grid size and the parameter mbod in galaxy.f for the maximum particle number that can be used.

Benchmarks

1000 particles...

See Also

unfio(1NEMO) , snapshot(5NEMO) , super(8NEMO)


Fellhauer et al (2000)

Author

M. Fellhauer, P. Kroupa, H. Baumgardt, R. Bien, C.M. Boily, R. Spurzem, N. Wassmer

History


??        V2.4 older version, w/ sticky particles, black holes, comoving coords
1997        V3.0 new improved, but without some previous features
4-mar-06    NEMO documented    PJT
18-mar-06    V3.3.1 imported for NEMO


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