Beyond Standard Model calculations with Sherpa

TL;DR

This paper introduces an automated framework within Sherpa for calculating and simulating beyond Standard Model processes, integrating model information, decay widths, and full event simulation including showers and hadronization.

Contribution

It provides a fully automated, integrated system for BSM calculations and simulations within Sherpa, utilizing FeynRules models and automating decay and event generation.

Findings

Automated computation of BSM cross sections and decays.

Integration of model info into Sherpa for full event simulation.

Supports arbitrary BSM scenarios with full hadron-level simulation.

Abstract

We present a fully automated framework as part of the Sherpa event generator for the computation of tree-level cross sections in beyond Standard Model scenarios, making use of model information given in the Universal FeynRules Output format. Elementary vertices are implemented into C++ code automatically and provided to the matrix-element generator Comix at runtime. Widths and branching ratios for unstable particles are computed from the same building blocks. The corresponding decays are simulated with spin correlations. Parton showers, QED radiation and hadronization are added by Sherpa, providing a full simulation of arbitrary BSM processes at the hadron level.