We discuss the theoretical bases that underpin the automation of the
computations of tree-level and next-to-leading order cross sections, of their
matching to parton shower simulations, and of the merging of matched samples
that differ by light-parton multiplicities. We present a computer program,
MadGraph5_aMC@NLO, capable of handling all these computations -- parton-level
fixed order, shower-matched, merged -- in a unified framework whose defining
features are flexibility, high level of parallelisation, and human intervention
limited to input physics quantities. We demonstrate the potential of the
program by presenting selected phenomenological applications relevant to the
LHC and to a 1-TeV $e^+e^-$ collider. While next-to-leading order results are
restricted to QCD corrections to SM processes in the first public version, we
show that from the user viewpoint no changes have to be expected in the case of
corrections due to any given renormalisable Lagrangian, and that the
implementation of these are well under way.

本文介绍了一个能自动化计算树级和次领阶截面的程序 MadGraph5_aMC@NLO，能匹配部分子级联，合并匹配样本。演示了该程序在 LHC 和 1TeV $e^+e^-$ 对撞机中的应用，并展示了其灵活性、高度并行和物理量输入的人为干预程度的特征。