PROGRAM SUMMARY
Title of program:
KORALZ, version 4.04
Catalogue identifier:
ADKX
Ref. in CPC:
124(2000)233
Distribution format: tar gzip file
Operating system: UNIX, HP-UX 10.2
High speed store required:
1MK words
Number of bits in a word:
32
Number of lines in distributed program, including test data, etc:
215118
Programming language used: Fortran
CPC Program Library subprograms used:
Cat. Id. Title Ref. in CPC ADKY GenLib, version 2.0 124(2000)238 ADKZ TTGlib, version 2.0 124(2000)243
Other versions of this program:
Cat. Id. Title Ref. in CPC ACBK KORALZ, version 3.8 66(1992)276 ACTI KORALZ, version 4.0 79(1994)503
Nature of physical problem:
Spin polarization of the tau in the process e+e- -> tau+tau-(etagamma),
tau+_ -> X+- is used as an important data point for precise tests of the
standard electroweak theory. The effects due to QED bremsstrahlung and
apparatus efficiency have to be subtracted from the data. The program
may be applied also to the production of u, d, s, c, b quarks and
neutrinos after appropriate redefinition of the coupling constants and
masses. It may be used, as well, to simulate the muon pair production
process. The precision of the program in the case of quarks and
electron neutrino is restricted. Certain classes of anomalous couplings
can be included for tau, q and nu final states.
Method of solution
The Monte Carlo simulation of the combined tau production and decay
process is used to calculate the spin effects and effects of radiative
corrections, including hard bremsstrahlung, simultaneously. Any
experimental cut and apparatus efficiency may easily be introduced by
rejecting some of the generated events.
Restrictions on the complexity of the problem
The incoming e+- and outgoing tau+- may have only longitudinal
polarizations. The total centre-of-mass energy is restricted to 240
GeV. The high precision of the program is assured only in the region of
the Z, where interference of bremsstrahlung from initial and final
states can be neglected.
Unusual features of the program
The distribution file includes the code for the programs GengLib,
version 2.0 (Comput. Phys. Commun. 124(2000)248 and TTGlib, version 2.0
(Comput. Phys. Commun. 124(2000)243).