Mixed Strong--Electroweak Radiative Corrections the Production of W/Z Bosons at the LHC

混合强电弱辐射校正大型强子对撞机中 W/Z 玻色子的产生

• 批准号: 414714711
• 负责人: Professor Dr. Stefan Dittmaier
• 金额: --
• 依托单位: Physikalisches Institut
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/414714711?language=en
• 关键词: Mixed; Strong; Electroweak; Radiative; Corrections

The Drell-Yan-like production of W and Z bosons is among the most important classes of particle reactions at the CERN Large Hadron Collider (LHC). As standard candle processes they are used in detector calibration, they offer high-precision measurements of the effective weak mixing angle and the W-boson mass, and finally provide a window to heavy new gauge bosons W' and Z' in high-energy tails of differential distributions. It is the aim of this proposal to calculate the next-to-next-to-leading-order corrections of mixed QCD-EW type to these processes, i.e. the ones of the order O(alpha_s alpha), which represent the largest unknown type of radiative corrections in fixed-order of perturbation theory. Beyond their direct phenomenological importance in the description of W/Z production, the results of these calculations will impact predictions for other process classes as well. On the one hand, concepts, techniques, and partial results may be taken over to other reactions; one the other, a comparison of the new full results to existing approximations will help to tune or to systematically improve the approximative combination of QCD and electroweak radiative corrections. Technically and conceptually, the challenging calculations are at the forefront of perturbative calculations for particle reactions, but widely build on existing methods such as integration-by-parts and differential equations for the calculation of massive two-loop Feyman diagrams or antenna subtraction for the treatment of infrared singularities in real-emission corrections. Nevertheless, certain aspects require generalizations and further developments of existing concepts, such as the gauge-invariant treatment of intermediate W/Z resonances via the complex-mass scheme.

W 和 Z 玻色子的类似 Drell-Yan 产生是 CERN 大型强子对撞机 (LHC) 中最重要的粒子反应类别之一。作为标准烛光过程，它们用于探测器校准，提供有效弱混合角和 W 玻色子质量的高精度测量，并最终为高能尾部中的重型新规范玻色子 W' 和 Z' 提供一个窗口的微分分布。本提案的目的是计算混合 QCD-EW 类型对这些过程的下一个到下一个前导阶校正，即 O(alpha_s alpha) 阶的校正，它代表最大的未知类型定阶微扰理论中的辐射修正。除了在描述 W/Z 生产中直接的现象学重要性之外，这些计算的结果还将影响对其他过程类别的预测。一方面，概念、技术和部分结果可以被其他反应所接管；另一方面，新的完整结果与现有近似值的比较将有助于调整或系统地改进 QCD 和电弱辐射校正的近似组合。从技术和概念上讲，具有挑战性的计算处于粒子反应微扰计算的最前沿，但广泛建立在现有方法的基础上，例如用于计算大规模双环费曼图的分部积分和微分方程或用于处理的天线减法实际发射校正中的红外奇点。然而，某些方面需要对现有概念进行概括和进一步发展，例如通过复质量方案对中间 W/Z 共振进行规范不变处理。