MadGraph 5 is the new version of the MadGraph matrix element generator, written in the Python programming language. It implements a number of new, efficient algorithms that provide improved performance and functionality in all aspects of the program. It features a new user interface, several new output formats including C++ process libraries for Pythia 8, and full compatibility with FeynRules for new physics models implementation, allowing for event generation for any model that can be written in the form of a Lagrangian. MadGraph 5 builds on the same philosophy as the previous versions, and its design allows it to be used as a collaborative platform where theoretical, phenomenological and simulation projects can be developed and then distributed to the high-energy community. We describe the ideas and the most important developments of the code and illustrate its capabilities through a few simple phenomenological examples.

https://link.springer.com/content/pdf/10.1007%2FJHEP06%282011%29128.pdf

MadGraph 5: going beyond

This paper presents a new event generator, ALPGEN, dedicated to the study of multiparton hard processes in hadronic collisions. The code performs, at the leading order in QCD and EW interactions, the calculation of the exact matrix elements for a large set of parton-level processes of interest in the study of the Tevatron and LHC data. The current version of the code describes the following final states: (W→f')Q+N jets (Q being a heavy quark, and f = l,q), with N ≤ 4;(Z/γ*→f)Q+N jets (f = l,ν), with N ≤ 4; W→f')+charm+N jets (f = l,q,N ≤ 5;W→f')+N jets (f = l,q and Z/γ*→f)+N jets (f = l,ν), with N ≤ 6; nW+mZ+lH+N jets, with n+m+l+N ≤ 8, N ≤ 3, including all 2-fermion decay modes of W and Z bosons, with spin correlations; Q+N jets, with t→bf' decays and relative spin correlations included where relevant, and N ≤ 6; QQ''+N jets, with Q and Q' heavy quarks (possibly equal) and N ≤ 4; HQ+N jets, with t→bf' decays and relative spin correlations included where relevant and N ≤ 4; N jets, with N ≤ 6. Parton-level events are generated, providing full information on their colour and flavour structure, enabling the evolution of the partons into fully hadronised final states.

/pdf/alpgen-a-generator-for-hard-multiparton-processes-in-4tuthlh5y0.pdf

ALPGEN, a generator for hard multiparton processes in hadronic collisions

Perturbative scattering amplitudes in Yang-Mills theory have many unexpected properties, such as holomorphy of the maximally helicity violating amplitudes. To interpret these results, we Fourier transform the scattering amplitudes from momentum space to twistor space, and argue that the transformed amplitudes are supported on certain holomorphic curves. This in turn is apparently a consequence of an equivalence between the perturbative expansion of = 4 super Yang-Mills theory and the D-instanton expansion of a certain string theory, namely the topological B model whose target space is the Calabi-Yau supermanifold

W.T. Giele

Papers

Recursive calculations for processes with n gluons

The Six Gluon Process as an Example of Weyl-Van Der Waerden Spinor Calculus

Multiple soft gluon radiation in parton processes

On relations between multi-gluon and multi-graviton scattering

Exact expressions for processes involving a vector boson and up to five partons