BRIDGE: Branching Ratio Inquiry/Decay Generated Events

TL;DR

BRIDGE is a software tool that automates decay processes in event simulations for particle physics, compatible with models like MSSM and integrated with MadGraph/MadEvent, improving efficiency and accuracy in decay chain generation.

Contribution

It introduces a flexible, automated method for simulating particle decays within event generators, supporting arbitrary models and decay chains, enhancing existing simulation workflows.

Findings

Accurately calculates decay widths for two and three body decays.

Effectively decays unstable particles in event files with complex decay chains.

Demonstrates compatibility and accuracy with MadGraph/MadEvent and MSSM models.

Abstract

We present the manual for the program BRIDGE: Branching Ratio Inquiry/Decay Generated Events. The program is designed to operate with arbitrary models defined within matrix element generators, so that one can simulate events with small final-state multiplicities, decay them with BRIDGE, and then pass them to showering and hadronization programs. BRI can automatically calculate widths of two and three body decays. DGE can decay unstable particles in any Les Houches formatted event file. DGE is useful for the generation of event files with long decay chains, replacing large matrix elements by small matrix elements followed by sequences of decays. BRIDGE is currently designed to work with the MadGraph/MadEvent programs for implementing and simulating new physics models. In particular, it can operate with the MadGraph implementation of the MSSM. In this manual we describe how to use BRIDGE, and present a number of sample results to demonstrate its accuracy.