Dipartimento di Fisica, Università di Pavia, and INFN, Sezione di Pavia, Via A. Bassi 6, 27100 Pavia, Italy.
Phys Rev Lett. 2013 Sep 20;111(12):121801. doi: 10.1103/PhysRevLett.111.121801. Epub 2013 Sep 17.
We compute the one-loop electroweak Sudakov corrections to the production process Z(νν)+n jets, with n=1, 2, 3, in pp collisions at the LHC. It represents the main irreducible background to new physics searches at the energy frontier. The results are obtained at the leading and next-to-leading logarithmic accuracy by implementing the general algorithm of Denner and Pozzorini in the event generator for multiparton processes alpgen. For the standard selection cuts used by the ATLAS and CMS Collaborations, we show that the Sudakov corrections to the relevant observables can grow up to -40% at sqrt[s ]= 14 TeV. We also include the contribution due to undetected real radiation of massive gauge bosons, to show to what extent the partial cancellation with the large negative virtual corrections takes place in realistic event selections.
我们计算了在 LHC 上 pp 碰撞中 Z(νν)+n 喷注(n=1,2,3)产生过程的单圈电弱 Sudakov 修正，这是能区前沿新物理搜索的主要背景。通过在多体过程的事件生成器 alpgen 中实现 Denner 和 Pozzorini 的通用算法，我们在领头阶和次领头阶对数精度下得到了结果。对于 ATLAS 和 CMS 合作组使用的标准选择 cuts，我们表明在 sqrt[s ]=14 TeV 时，相关可观测量的 Sudakov 修正可以增长到-40%。我们还包括了由于未检测到的大质量规范玻色子的真实辐射而产生的贡献，以表明在实际的事件选择中，大的负虚修正与部分抵消的程度。
