Package for calculations and simplifications of expressions with Dirac matrices (MatrixExp)

This paper describes a package for calculations of expressions with Dirac matrixes. Advantages to existing similar packages are described. MatrixExp package is intended for simplification of complex expressions involving γ-matrixes, providing such tools as automatic Feynman parameterization, integration in d-dimensional space, sorting and grouping of results in a given order. Also, in comparison with existing similar package Tracer, presented package MatrixExp has more enhanced input possibility. User-available functions of MatrixExp package are described in detail. Also an example of calculation of Feynman diagram for process b → sγg with application of functions of MatrixExp package is presented. PACS: 13.10.+q, 13.90.+i, 07.05.Bx, 14.40.Nd email: [email protected] The package is available at http://www.yerphi.am/matrixexp.html