The trilinear Higgs coupling ${\lambda }_{hhh}$ is crucial for determining the structure of the Higgs potential and for probing possible effects of physics beyond the standard model. Focusing on the two-Higgs-doublet model as a concrete example, we identify parameter regions in which ${\lambda }_{hhh}$ is significantly enhanced with respect to the standard model. Taking into account all relevant corrections up to the two-loop level, we show that already current experimental bounds on ${\lambda }_{hhh}$ rule out significant parts of the parameter space that would otherwise be unconstrained. We illustrate the interpretation of the results on ${\lambda }_{hhh}$ for a benchmark scenario. Similar results are expected for wide classes of models with extended Higgs sectors.

中文翻译：

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三线性希格斯耦合对扩展希格斯扇区的新约束

三线性希格斯耦合${\lambda }_{HHH}$对于确定希格斯势的结构和探索超出标准模型的物理可能影响至关重要。以 two-Higgs-doublet 模型为具体示例，我们确定参数区域，其中${\lambda }_{HHH}$相对于标准模型显着增强。考虑到双循环级别的所有相关修正，我们表明当前的实验范围已经在${\lambda }_{HHH}$排除参数空间的重要部分，否则这些部分将不受约束。我们说明了对结果的解释${\lambda }_{HHH}$对于基准场景。对于具有扩展的希格斯扇区的大量模型，预计会有类似的结果。