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arXiv · 2412.19620

$\mu^-\mu^+\to {\nu_\mu}\bar{\nu}_\mu t\bar{t}H$ amplitudes in the Feynman-diagram gauge

Ya-Juan Zheng
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Abstract

We study the process $\mu^-\mu^+\to {\nu_\mu}\bar{\nu}_\mu t\bar{t}H$ with complex CP violating $ttH$ couplings in the SMEFT with a dimension-6 operator. When the amplitudes are expressed in the Feynman-Diagram gauge, the dominance of the total cross section via the weak boson fusion diagrams is manifest. The high energy behaviour is dictated by the higher-dimensional vertices in the dimension-6 SMEFT operator. These properties are not manifest in the unitary gauge because of subtle cancellation among diagrams.

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Ya-Juan Zheng. 2024-12-27. $\mu^-\mu^+\to {\nu_\mu}\bar{\nu}_\mu t\bar{t}H$ amplitudes in the Feynman-diagram gauge. https://doi.org/10.1051/epjconf/202431501028

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