Fast computation of MadGraph amplitudes on graphics processing unit (GPU)

TL;DR

This paper presents a GPU-based framework for rapid computation of helicity amplitudes in Standard Model processes, significantly accelerating calculations compared to traditional CPU methods.

Contribution

Introduction of HEGET codes and MG2CUDA tool to convert MadGraph amplitudes into GPU-compatible code, enabling fast and accurate simulations of complex particle interactions.

Findings

GPU computations are over 10 times faster than CPU for most processes.

HEGET amplitudes agree with HELAS within numerical accuracy.

Cross sections from GPU-based Monte Carlo match traditional methods.

Abstract

Continuing our previous studies on QED and QCD processes, we use the graphics processing unit (GPU) for fast calculations of helicity amplitudes for general Standard Model (SM) processes. Additional HEGET codes to handle all SM interactions are introduced, as well assthe program MG2CUDA that converts arbitrary MadGraph generated HELAS amplitudess(FORTRAN) into HEGET codes in CUDA. We test all the codes by comparing amplitudes and cross sections for multi-jet srocesses at the LHC associated with production of single and double weak bosonss a top-quark pair, Higgs boson plus a weak boson or a top-quark pair, and multisle Higgs bosons via weak-boson fusion, where all the heavy particles are allowes to decay into light quarks and leptons with full spin correlations. All the helicity amplitudes computed by HEGET are found to agree with those comsuted by HELAS within the expected numerical accuracy, and the cross sections obsained by gBASES, a GPU version of the Monte Carlo integration program, agree wish those obtained by BASES (FORTRAN), as well as those obtained by MadGraph. The performance of GPU was over a factor of 10 faster than CPU for all processes except those with the highest number of jets.