SOPHIA, Monte Carlo simulations of photohadronic processes in astrophysics. A. Muecke, R. Engel, J.P. Rachen, R.J. Protheroe, T. Stanev.

Title of program: SOPHIA 2.0
Catalogue identifier: ADLB
Ref. in CPC: 124(2000)290
Distribution format: tar gzip file
Operating system: UNIX, Linux, Open-VMS
High speed store required: 1MK words
Number of bits in a word: 64
Number of lines in distributed program, including test data, etc: 17290
Programming language used: Fortran
Computer: DEC-Alpha workstation

Nature of physical problem:
Simulation of minimum bias photoproduction for astrophysical applications.

Method of solution
Monte Carlo simulation of individual events for given nucleon and photon energies, photon energies are sampled from various distributions.

Restrictions on the complexity of the problem
Incident ambient photon fields limited to power law and blackbody spectra so far. No tests were done for center-of-mass energies sqrt(s) >= 1000 GeV.

Typical running time
10000 events at a center-of-mass energy of 1.5 GeV require a typical CPU time of about 75 seconds.

Unusual features of the program
Other programs used in SOPHIA in modified form: RNDM, processor independent random number generator based on Ref [1]; JETSET 7.4, Lund Monte Carlo for jet fragmentation [2]; DECSIB, SIBYLL routine which decays unstable particles [3].


 [1] G. Marsaglia, A. Zaman, Toward a universal random number generator, 
     Florida State Univ., Preprint FSU-SCRI-87-70, 1987.                 
 [2] T. Sjostrand, Comp. Phys. Commun. 82 (1994) 74.                     
 [3] R.S. Fletcher, T.K. Gaisser, P. Lipari, T. Stanev, Phys. Rev. D 50  
     (1994) 5710.