MaRTIn – Massive Recursive Tensor Integration

We present MaRTIn , an extendable all-in-one package for calculating amplitudes up to two loops in an expansion in external momenta or using the method of infrared rearrangement. Renormalisable and non-renormalisable models can be supplied by the user; an implementation of the Standard Model is included in the package. In this manual, we discuss the scope and functionality of the software, and give instructions of its use. PROGRAM SUMMARY Program Title: MaRTIn CPC Library link to program files: https://doi.org/10.17632/bf96rjxnky.1 Developer's repository link: https://gitlab.com/manstam/martin Licensing provisions: GPLv3 Programming language: FORM , python Nature of problem: The computation of tree-level processes and quantum corrections in perturbation theory requires several complicated steps. This potentially includes diagram generation, resolving gauge and flavour algebras, spinor contractions, tensor reduction, application of integration-by-parts relations and scalar integration. Solution method: Arbitrary relativistic QFTs can be defined via field contents and Feynman rules. Additional information regarding the desired amplitude and compuation are supplied by the user. Using these inputs, all steps of the calculation are conducted automatically. Additional comments including restrictions and unusual features: MaRTIn is designed as an extensible all-in-one solution, no additional glue code is required. Currently, computations may be conducted up to two loops with either an expansion in external momenta or infrared rearrangement via a mass parameter. Several options for the treatment of γ 5 are implemented.