LanHEP - a package for automatic generation of Feynman rules in gauge models

TL;DR

LanHEP is a software package that automates the derivation of Feynman rules from gauge-invariant Lagrangians, facilitating calculations in particle physics models like QED, QCD, and the Standard Model.

Contribution

It introduces a user-friendly tool for automatically generating Feynman rules from gauge model Lagrangians, streamlining theoretical calculations.

Findings

Successfully generates Feynman rules for various models

Integrates with CompHEP for process calculations

Demonstrated on QED, QCD, and Standard Model

Abstract

We consider the general problem of derivation of the Feynman rules for the matrix elements in momentum representation from the given Lagrangian in coordinate space invariant under the transformation of some gauge group. LanHEP package presented in this paper allows to define in a convenient way the gauge model Lagrangian in canonical form and then to generate automatically the Feynman rules that can be used in the following calculation of the physical processes by means of CompHEP package. The detailed description of LanHEP commands is given and several examples of LanHEP applications (QED, QCD, Standard Model in the t'Hooft-Feynman gauge) are presented.