Recola: Recursive Computation of 1-Loop Amplitudes

Last updated: Nov 07, 2023


Recola is a Fortran95 computer program for the automated generation and numerical computation of tree and one-loop amplitudes at next-to-leading order (EW, QCD) in the Standard Model (SM) and Beyond the SM (BSM).

The following sections cover the installation and basic usage of the tools.

Recola & Recola2

Currently two separately maintained versions exist:

  • Recola is the original version (a.k.a Recola1) which is tailored for computations within the Standard Model in the ‘t Hooft–Feynman gauge.

  • Recola2 is the successor of Recola, a generalized version for computations in the SM, for BSM theories and SMEFT.

A list of releases and the release history can be found here.


This section describes the building and installation steps of Recola and Recola2.


This section describes the first steps in using Recola and Recola2 (requires the installation). We go through the example of using the demo files and setting up new demo files.

Recola2 model files

In Recola2 model files are linked to the Recola2 library. We describe the models and their configuration and compilations steps for a manual installation (not required when using the Recola2-Collier installation).

API Docs

We list all functions provided by the library accessible to the user. This section is still under construction.

Should you be using Recola for publication you are kindly asked to cite the relevant references.


For questions, comments or bug reports, please send an email to the Recola developers.


Former authors: Stefano Actis, Lars Hofer, Andreas Scharf

We gratefully thank

  • Benedikt Biedermann, Robert Feger, Mathieu Pellen and Mauro Chiesa

for their valueable contributions to Recola.