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Manuscript Title: An event generator for interactions between hadrons and nuclei: FRITIOF version 7.0.
Authors: H. Pi
Program title: FRITIOF version 7.0
Catalogue identifier: ACHY_v1_0
Distribution format: gz
Journal reference: Comput. Phys. Commun. 71(1992)173
Programming language: Fortran.
Computer: DECstation 3100.
Operating system: ULTRIX RISC 4.2.
RAM: 90K words
Word size: 32
Keywords: Particle physics, Elementary, Event simulation, Monte carlo, Hadrons, Nuclei, Interactions, Gluon radiation, Rutherford parton Scattering, Fragmentation.
Classification: 11.2.

Other versions:
Cat Id Title Reference
AATH_v1_0 FRITIOF version 1.6 CPC 43(1987)387

Nature of problem:
In high energy hadron-hadron, hadron-nucleus and nucleus-nucleus collisions multi particle final states are produced. The bulk of the particles produced are at low PT. Strong interaction processes are generally non-perturbative and can not yet be fully understood in terms of quantum chromodynamics (QCD). As energy gets higher, some high-PT phenomena begin to appear in accordance with the perturbative calculations in QCD. The problem is to consistently connect the high PT Rutherford scattering and the ensuing gluonic bremsstrahlung with a nonperturbative model for the low PT phenomena.

Solution method:
A collision between two hadrons is modelled by many momentum transfers. The possibility of one of the momentum transfers corresponding to large PT scattering is properly treated according to QCD. After the exchange of momenta the hadrons are assumed to become two excited string states, which emit further gluonic radiations in a colour dipole approach to the QCD parton branching. The final hadronization is performed by using the Lund string fragmentation model. Collisions with nuclei are assumed to involve only independent collisions between the constituent nucleons.

The program is not supposed to be applicable at collision center-of-mass energies (sqrt(s)) below 10 GeV. At very high energies (sqrt(s) in the TeV range), especially for heavy ion collisions, certain arrays need to be expanded to accomodate the large number of particles produced.

Running time:
Depends on the type of collision and energy. Some examples:
 pp                sqrt (s) = 30 GeV:      Approx. 90 events/min         
 p(bar)p           sqrt (s) = 900 GeV:     Approx. 70 events/min         
 p(bar)p           sqrt (s) = 40 TeV:      Approx. 30 events/min         
 16    197                                                               
   O +    Au       Plab   = 200 A GeV/c:   ~6  events/min