标题： LHC上极化Z玻色子对产生和衰变的精确标准模型预测 显示英文标题

标题： Precise Standard-Model predictions for polarised Z-boson pair production and decay at the LHC

摘要： 在标准模型中，为具有极化弱电玻色子的过程提供精确的理论预测对于更深入地理解电弱对称性破缺机制以及增强对潜在新物理效应的敏感性至关重要。 受到利用LHC数据对双玻色子过程的极化分析数量迅速增加的推动，我们对具有四个带电轻子衰变通道的两个极化Z玻色子的综合产生进行了全面研究。 我们详细比较了通过各种依赖不同信号定义策略的蒙特卡洛程序获得的固定阶预测，通过对比极化结果与非极化和完全离壳的结果来评估非共振和干涉效应。 首次，我们完成了NNLO QCD和NLO EW修正的结合，在LHC上为极化Z玻色子对设置了新的状态-of-the-art微扰精度。 通过对通常用于实验分析的事件生成器计算结果的仔细检查，调查了部分子 showers 匹配和多喷注合并的影响。 在现实的标识设置中讨论了积分和微分结果，并与公开可用的 ATLAS 结果进行了比较。 显示英文摘要

摘要： Providing accurate theoretical predictions in the Standard Model for processes with polarised electroweak bosons is crucial to understand more in-depth the electroweak-symmetry breaking mechanism and to enhance the sensitivity to potential new-physics effects. Motivated by the rapidly increasing number of polarisation analyses of di-boson processes with LHC data, we carry out a comprehensive study of the inclusive production of two polarised Z bosons in the decay channel with four charged leptons. We perform a detailed comparison of fixed-order predictions obtained with various Monte Carlo programs which rely on different signal-definition strategies, assessing non-resonant and interference effects by contrasting polarised results with unpolarised and full off-shell ones. For the first time, we accomplish the combination of NNLO QCD and NLO EW corrections, setting the new state-of-the-art perturbative accuracy for polarised Z-boson pairs at the LHC. The impact of parton-shower matching and multi-jet merging is investigated by scrutinising calculations obtained with event generators that are typically used in experimental analyses. Integrated and differential results are discussed in a realistic fiducial setup and compared to publicly available ATLAS results.