PROGRAM SUMMARY
Title of program:
eett6f v. 1.0
Catalogue identifier:
ADRD
Ref. in CPC:
151(2003)339
Distribution format: tar gzip file
Operating system: Unix/Linux
High speed store required:
1MK words
Number of bits in a word:
32
Number of lines in distributed program, including test data, etc:
8970
Keywords:
e+e- annihilation, SM, Lowest order six-fermion reactions,
ttbar production and decay, Elementary particle physics,
Event simulation.
Programming language used: Fortran
Computer:
PC 800 MHZ Pentium III .
Nature of physical problem:
Description of e+e- -> 6 fermions processes relevant for a ttbar-pair
production and decay at centre of mass energies typical for linear
colliders; all six fermion reactions containing a b and bbar quarks and
four other fermions of different flavours with a complete set of the
Feynman diagrams in the lowest order of SM.
Method of solution:
Matrix elements are calculated numerically with the helicity amplitude
method. Constant widths of unstable particles are implemented by
modifying mass parameters in corresponding propagators. The phase space
integration is performed numerically utilizing a multi-channel Monte
Carlo method.
Restrictions:
Reactions containing fermions of the same flavour are not treated. No
higher order effects are taken into account, except for assuming the
fine structure constant and the strong coupling at appropriate scale and
partial summation of the one particle irreducible loop corrections by
introducing fixed widths of unstable particles.
Typical running time:
The running time depends strongly on a desired precision of the result.
The results of the appended test run have been obtained on a 800 MHz
Pentium III processor with the use of Absoft FORTRAN 90 compiler in 490
seconds. In order to obtain a precision level below one per mille a few
million calls to the integrand are required. This results in a typical
running time of several hours. The running time becomes much shorter
for approximated cross sections.