UFO - The Universal FeynRules Output

TL;DR

The paper introduces the Universal FeynRules Output (UFO), a flexible, modular, and generator-agnostic model format for automated matrix-element generation, encoded as Python modules for easy integration.

Contribution

It presents the UFO format, enabling compatibility across multiple generators and simplifying model sharing through Python-based encoding.

Findings

UFO supports multiple matrix-element generators.

The format is flexible and modular, accommodating various particle interactions.

An interface for FeynRules automates UFO model generation.

Abstract

We present a new model format for automatized matrix-element generators, the so- called Universal FeynRules Output (UFO). The format is universal in the sense that it features compatibility with more than one single generator and is designed to be flexible, modular and agnostic of any assumption such as the number of particles or the color and Lorentz structures appearing in the interaction vertices. Unlike other model formats where text files need to be parsed, the information on the model is encoded into a Python module that can easily be linked to other computer codes. We then describe an interface for the Mathematica package FeynRules that allows for an automatic output of models in the UFO format.