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Manuscript Title: EXOTIC - a heavy fermion and excited fermion Monte Carlo generator for e+e- physics. (Corrected version - see Comp. Phys. Commun. 133(2000)136).
Authors: R. Tafirout, G. Azuelos
Program title: EXOTIC
Catalogue identifier: ADLJ_v1_0
Distribution format: gz
Journal reference: Comput. Phys. Commun. 126(2000)244
Programming language: Fortran.
Computer: HP 9000/700 series, SUN Ultra Sparc series, DEC alpha, SGI, Pentium.
Operating system: HPUX, Solaris, VAX/VMS, IRIX, Linux.
RAM: 2.5M words
Word size: 32
Keywords: Elementary particle physics, High energy electron Positron collisions, Heavy fermions, Excited fermions, Monte Carlo generator, Standard model, Compositeness, Exotic fermions, Event simulation.
Classification: 11.2.

Subprograms used:
Cat Id Title Reference
ACTU_v1_0 PYTHIA 5.7 AND JETSET 7.4 CPC 82(1994)74
ACTA_v1_0 PHOTOS version 2.0 CPC 79(1994)291

Revision history:
Type Tit le Reference
correction 000ACORRECTION 08/2000 See below

Nature of problem:
Cross section and event generation for e+e- -> FFbar (pair production), and e+e- -> fbarF (single production) of heavy or excited fermions which decay into their light standard fermion partner and a gauge boson. The processes generated account for full spin correlations in the production and decay processes, with inclusion of initial and final state radiation (see chapter 3 for details). An interface to JETSET allows fragmentation and hadronization of final quarks.

Solution method:
For fast Monte Carlo generation of unweighted events, some distributions are calculated once, then sampled. Event sampling is done only at the last stage, after evaluation of the total polarized differential cross section according to its maximum value.

Restrictions:
The program is specifically designed for high energy e+e- collisions, i.e. at LEP 2 and NLC. The program does not include cascade decays, where a heavy fermion decays into a lighter heavy fermion, which in turn decays also into a light standard fermion and a gauge boson.

Unusual features:
REAL*8 and COMPLEX*8 declarations are used. For some processes, the program uses the GENBOD routine, from the CERN program library [4] (RAMBO is not efficient when outgoing particles have masses greater than the half of the available energy, which could be the case for a charged heavy lepton decaying into a neutral heavy lepton and a virtual or real W boson). The random number generator used is RANMAR from the CERN Program Library.

Running time:
With initial state radiation and full spin correlations, the generation of 5000 unweighted events e+e- -> FFbar without fragmentation and hadronization of final quarks takes on average 205 seconds in CPU time on an HP 9000/755 (275 seconds when including fragmentation and hadronization).

References:
[1] R. Kleiss, W.J. Sterling and S.D. Ellis, Comp. Phys. Comm. 40 (1986) 359.
[2] T. Sjostrand, Comp. Phys. Comm. 82 (1994) 74.
[3] E. Barberio and Z. Was, Comp. Phys. Comm. 79 (1994) 291.
[4] CERN Program Library, CN Division, CERN, Geneva.

CORRECTION SUMMARY
Manuscript Title: EXOTIC - a heavy fermion and excited fermion Monte Carlo generator for e+e- physics.
Authors: R. Tafirout, G. Azuelos
Program title: 000ACORRECTION 08/2000
Catalogue identifier: ADLJ_v1_0
Distribution format: gz
Journal reference: Comput. Phys. Commun. 133(2000)136
Classification: 11.2.