本文提出在 Type-I 2HDM 中，通过电弱多希格斯产生过程可在多 b 末态同时观测新的中性与带电希格斯玻色子，为 LHC 验证该模型提供确凿信号。
摘要：
在标准模型（SM）中额外引入一个希格斯二重态，可得到双希格斯二重态模型（2HDM）。对 SM 费米子在 $\mathbb{Z}_2$ 对称性下进行特定电荷分配，可得到 Type-I 2HDM。Type-I 2HDM 的一个关键特征是，当额外希格斯玻色子与 SM 费米子的耦合被压低时，它们都可以是疏费米子的。因此，所有新的希格斯态都可以相当轻，约为 100 GeV 或更低，而不会与当前直接希格斯玻色子搜寻和 $B$ 物理测量的数据相冲突。在最近的一项研究（参考文献~\cite{Mondal:2023wib}，也是本文的基础）中，我们确认该模型中的新中性希格斯玻色子和带电希格斯玻色子都可以在多 $b$ 末态中被同时观测到。对我们结果的实验验证将清楚地表明，自然界中真实的希格斯部分确实是 Type-I 2HDM。
英文摘要：
Extending the Standard Model (SM) by one additional Higgs doublet leads to the Two-Higgs Doublet Model (2HDM). A specific charge assignment of the SM fermions under the $\mathbb{Z}_2$ symmetry leads to the Type-I 2HDM. A key feature of the Type-I 2HDM is that all the additional Higgs bosons can be fermiophobic, when their couplings to the SM fermions are suppressed. As a result, all the new Higgs states can be fairly light, $\sim$100 GeV or less, without being in conflict with the current data from the direct Higgs boson searches and the $B$-physics measurements. In a recent study Ref.~\cite{Mondal:2023wib}, which this proceeding is based on, we established that the new neutral as well as the charged Higgs bosons in this model can all be simultaneously observable in the multi-$b$ final state. An experimental validation of our results would be a clear indication that the true underlying Higgs sector in nature is the Type-I 2HDM.
Indian Institute of Science Education and Research - Bhopal（印度科学教育研究所博帕尔分校）；Instituto Superior Técnico, Universidade de Lisboa（里斯本大学高等技术学院）；Korea Institute for Advanced Study（韩国高等研究院）
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