Recently, the ATLAS and CMS collaborations jointly announced the first evidence of the rare Higgs boson decay channel $H\to Z\gamma$, with a ratio of $2.2\pm 0.7$ times the leading order standard model (SM) prediction. In order to face this challenge, it is urgent to produce an even more accurate calculation within the SM. To this end, we calculate in this paper the next-to-leading order (NLO) electroweak (EW) corrections to the $H\to Z\gamma$ process, in which the NLO quantum chromodynamics (QCD) corrections were found tiny. Our calculation finds that the inclusion of NLO EW corrections greatly enhances the prediction reliability. To tame the theoretical uncertainty, we adopt five different renormalization schemes. Combining our result with previous NLO QCD corrections and the signal-background interference, we conclude that the excess in $H\to Z\gamma$ cannot be explained within the SM. In fact, the incompatibility between the SM prediction and the LHC measurement of the concerned process is exacerbated upon considering the higher order EW corrections, which implies that something beyond the SM could be involved.

中文翻译：

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希格斯玻色子稀有衰变过程H→Zγ的双环电弱校正


近日，ATLAS与CMS合作联合公布了稀有希格斯玻色子衰变通道的首个证据 $H\to Z\gamma$ ，比例为 $2.2\pm 0.7$ 乘以主阶标准模型 (SM) 预测。为了应对这一挑战，迫切需要在 SM 内产生更精确的计算。为此，我们在本文中计算了对 $H\to Z\gamma$ 过程中，非线性光学量子色动力学 (QCD) 校正发现很小。我们的计算发现，包含 NLO EW 修正大大提高了预测的可靠性。为了克服理论上的不确定性，我们采用了五种不同的重正化方案。将我们的结果与之前的 NLO QCD 校正和信号背景干扰相结合，我们得出结论： $H\to Z\gamma$ 无法在SM中解释。事实上，考虑到更高阶的电子战修正，SM 预测和相关过程的 LHC 测量之间的不兼容性会加剧，这意味着可能涉及 SM 之外的东西。