The LanHEP program for Feynman
rules generation in momentum representation is presented. It reads
the Lagrangian written in the compact form close to one used in publications.
It means that Lagrangian terms can be written
with summation over indices of broken symmetries and using special symbols for
complicated expressions, such as covariant derivative and
strength tensor for gauge fields. The output
is Feynman rules in terms of physical fields and independent parameters.
This output can be written in LaTeX format and in the form of
model files, which allows one to start calculations of processes in
the new physical model. Although this job is rather
straightforward and can
be done manually, it requires careful calculations and in the modern
theories with many particles and vertices can lead to errors and
The program allows one to introduce into CompHEP new gauge theories as well
as various anomalous terms.
To install LanHEP on your computer, you should get the
archive file (see below) and unpack it. The archive contains
the C source files. To create the executable
file lhep , type 'make`. When the LanHEP is
complied, remove source files by typing 'make clean`.
The archive also contains the directory
mdl with startup file and examples
for several physical models.
Add the directory containing LanHEP
to your PATH environment variable. Than LanHEP can be started from any
other directory, it can find automatically files from the