  grc4f is a Monte-Carlo package for generating e+e- to 4-fermion processes in
the standard model. All of the 76 LEP-2 allowed fermionic final state processes
evaluated at tree level are included in version 1.0. grc4f addresses event
simulation requirements at e+e- colliders such as LEP and up-coming linear
colliders. Most of the attractive aspects of grc4f come from its link to the
GRACE system: a Feynman diagram automatic computation system. The GRACE system
has been used to produce the computational code for all final states, giving a
higher level of confidence in the calculation correctness. Based on the
helicity amplitude calculation technique, all fermion masses can be kept finite
and helicity information can be propagated down to the final state particles.
The phase space integration of the matrix element gives the total and
differential cross sections, then unweighted events are Generated. Initial
state radiation (ISR) corrections are implemented in two ways, one is based on
the electron structure function formalism and the second uses the parton shower
algorithm called QEDPS. The latter can also be applied for final state
radiation (FSR) though the interference with the ISR is not yet taken into
account. Parton shower and hadronization of the final quarks are performed
through an interface to JETSET. Coulomb correction between two intermediate
W's, anomalous coupling as well as gluon contributions in the hadronic
processes are also included.
