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arXiv · 2209.07612

Two-Loop Electroweak Corrections with Fermion Loops to $e^+ e^- \to ZH$

Ayres Freitas·Qian Song
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Abstract

We present a complete calculation of the next-to-next-to-leading (NNLO) electroweak corrections involving closed fermion loops to the $e^+ e^- \to ZH$ process. This has been achieved by using a semi-numerical technique for the two-loop vertex and box diagrams, which is based on Feynman parameters and dispersion relations for one of the two sub-loops. UV divergences are treated with suitable subtraction terms. Numerical results for the unpolarized differential and integrated cross-section at center-of-mass energy $\sqrt{s}=240~\text{GeV}$ are provided. Combining the NNLO contributions with one and two closed fermions loops, they are found to increase the NLO cross-section by 0.7\%.

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Ayres Freitas, Qian Song. 2023-01-06. Two-Loop Electroweak Corrections with Fermion Loops to $e^+ e^- \to ZH$. https://doi.org/10.1103/physrevlett.130.031801

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