现有的微扰QCD计算结合了硬过程矩阵元和Parton Shower Monte Carlo程序，其特点是硬过程矩阵元的计算经常超过首阶（LO），即包括完全的次首阶（NLO），甚至次首阶（NNLO）修正，而Parton Shower只在首阶（LO）。我们在这里报告的工作正在进行中，证明了构建Parton Shower Monte Carlo（PSMC）的可行性，具有完整的非线性光学校正QCD演化相对于对数的因式分解尺度。这项工作目前涵盖了非单态子集的费曼图有助于上述QCD的演变。应该强调的是，我们的方法的非线性QCD演化是唯一的，这是给洞察到完全未整合的相空间。然而，在包容性层面上，我们的实施完全符合NLO DG演变的标准包容性图片。我们的新方法（包括非线性光学单线图后）提供了一个完整的方法相结合的mammed和固定阶微扰QCD计算超出LO的形式适合于MC实现，现有的替代。第一个实际应用将包括在强子-强子对撞机和轻子-强子对撞机中W/Z产生过程的蒙特卡罗发生器。
英文摘要：
Presently available perturbative QCD calculations combining hard process matrix element with the Parton Shower Monte Carlo programs feature hard process matrix element calculated often beyond the leading order (LO), that is including complete next-to-leading-order (NLO), or even next-to-next-to-leading-order (NNLO) corrections, while Parton Shower is only at the leading order (LO). We report here on a work in progress which demonstrate feasibility of constructing Parton Shower Monte Carlo (PSMC) featuring complete NLO corrections to QCD evolution with respect to the logarithm of the factorization scale. This effort presently covers non-singlet subset of Feynman diagrams contributing to the above QCD evolution. It should be stressed that our approach to the NLO QCD evolution is exclusive, that is giving insight into the fully unintegrated phase space. However, at the inclusive level our implementation agrees exactly with the standard inclusive picture of the NLO DGLAP evolution. Our new approach (after including NLO singlet diagrams) provides a complete method of combining the resummed and fixed order perturbative QCD calculations beyond the LO in a form suitable for the MC implementation, an alternative to the existing ones. First practical applications will include Monte Carlo generators for W/Z production processes in hadron-hadron colliders and lepton-hadron colliders.
The $NLO$ production of the $W^{\pm}$ and $Z^0$ vector bosons via hadron collisions in the frameworks of $KMR$ and $MRW$ unintegrated parton distribution functions
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