大型强子对撞机（LHC）上WWγ产生过程的次主阶量子色动力学（NNLO QCD）修正
NNLO QCD corrections to $WWγ$ production at the LHC
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中文总结 AI 辅助
本研究计算LHC上WWγ产生的NNLO QCD修正，纳入W玻色子轻子衰变与离壳效应，经Zγ参考过程验证，13 TeV下NNLO修正提升NLO结果约16%，不确定性显著降低。
中文摘要 AI 辅助
三玻色子产生过程对研究四阶规范玻色子耦合至关重要。我们计算了大型强子对撞机（LHC）上WWγ产生过程的量子色动力学次主阶（NNLO）辐射修正，完整包含W玻色子的轻子衰变及离壳效应。该计算除双圈振幅的有限部分采用软光子近似评估外，其余均为精确计算。我们以Zγ产生为参考过程验证该方法，利用其精确双圈振幅的可用性对近似结果给出保守误差估计，再将其应用于WWγ产生。在质心能量√s=13 TeV的典型选取截断下，NNLO修正使次主阶（NLO）结果提升约16%，微扰不确定性降至±4%水平；软近似带来的不确定性仅为千分之几，在基准截面及最相关的微分分布中，均远小于残余微扰不确定性。
英文摘要
Triboson production processes are crucial to study quartic gauge-boson couplings. We present the computation of the radiative corrections to $WWγ$ production at the next-to-next-to-leading order (NNLO) in QCD. The leptonic decays of the $W$ bosons and off-shell effects are fully included. The calculation is exact, apart from the finite part of the two-loop amplitudes, which is evaluated in a soft-photon approximation. We validate our approach by using $Zγ$ production as a reference process, where we take advantage of the availability of the exact two-loop amplitudes to derive a conservative error estimate for our approximation, and then apply it to $WWγ$ production. For typical selection cuts, at the centre-of-mass energy $\sqrt{s}=13$ TeV, the NNLO corrections increase the next-to-leading order (NLO) result by about $16\%$, and the perturbative uncertainties are reduced to the $\pm4\%$ level. The uncertainty from the soft approximation turns out to be at the few per mille level, largely subdominant compared to the residual perturbative uncertainties, both for the fiducial cross section and the most relevant differential distributions.
