PROGRAM SUMMARY
Title of program:
KoralW, version 1.51
Catalogue identifier:
ADOZ
Ref. in CPC:
140(2001)475
Distribution format: tar gzip file
Operating system: UNIX, Linux version 6.x and 7.x
High speed store required:
25MK words
Number of lines in distributed program, including test data, etc:
606760
Keywords:
Radiative corrections, Initial-state radiation (ISR),
O(alpha) electroweak (EW) corrections, Leading-logarithmic
(LL) approximation, Heavy boson W, Four-fermion processes,
Monte Carlo (MC) simulation/generation, Quantum
electrodynamics (QED), Quantum chromodynamics (QCD),
Yennie-Frautschi-Suura (YFS) exponentiation,
Standard Model (SM), LEP2, Next-generation,
Linear colliders (LC), Elementary particle physics,
Event simulation.
Programming language used: Fortran
Computer:
PC Pentium III, 800 MHz .
Other versions of this program:
Cat. Id. Title Ref. in CPC ADCT KORALW 1.02 94(1996)215 ADKJ KoralW, version 1.42 119(1999)272
Nature of physical problem:
The precise study of W-pair production and decay at LEP2 requires both
non-double-resonant and O(alpha) corrections. So far each of these
corrections is available as a separate Monte Carlo program and there is
no Monte Carlo that could simulate in a complete way both effects at the
same time. Such a MC event generator would be of importance, for
example, for apparatus simulations or Monte Carlo based fits. The
previous version of KoralW [1] included all non-double-resonant
corrections to all double-resonant four-fermion processes in e+e-
annihilation. The present version 1.51. allows, for the first time
ever, the inclusion on an event-per-event basis of the respective
O(alpha) corrections generated at the same time by the independently
running Monte Carlo program YFSWW3 [2], as well as a reweighting of any
earlier generated events with modified parameter sets.
Method of solution:
The Monte Carlo method used to simulate the all four-fermion final-state
processes in e+e- collisions in the presence of multiphoton
initial-state radiation has not changed since version 1.42 [1]. Adding
the O(alpha) corrections generated by YFSWW3 is done at the level of the
UNIX/Linux operating system with the help of the FIFO mechanism ("named
pipes").
Restrictions:
For KoralW as in version 1.42 [1]; for KoralW&YFSWW3 as in [1,2].
Typical running time:
Approximate times on a PC Pentium III @ 800 MHz for cuts as described in
this article: 5 minutes per 1000 constant-weight CCall events (KoralW
stand-alone); 50 minutes per 1000 constant-weight CCall events with the
O(alpha) correction (the CMC KoralW&YFSWW3, max. weight for rejection
increased by a factor 2).
References:
[1] S. Jadach et al., Comput. Phys. Commun. 119 (1999) 272. [2] S. Jadach et al., The Monte Carlo event generator YFSWW3 version 1.16 for W-pair production and decay at LEP2/LC energies, Preprint CERN-TH/2001-017, UTHEP-01-0101, January 2001, hep-ph/0103163; Comput. Phys. Commun. 140 (2001) 432.