Higgs interference effects in top-quark pair production in the 1HSM
Higgs interference effects in top-quark pair production in the 1HSM
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发表时间：
2023-09
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通讯作者：
A. Banfi;N. Kauer;Alexander Lind;J. Lindert;Ryan Wood
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作者：
A. Banfi;N. Kauer;Alexander Lind;J. Lindert;Ryan Wood
在标准模型的1-Higgs单重态扩展中，加入一个重Higgs玻色子h_2 $与轻Higgs玻色子h_1 $混合，对过程pp \;（\to \{ h_1，h_2 \}）\to t\bar{t} + X$进行了次领先阶（NLO）研究.这一过程受到环诱导希格斯介导的振幅和QCD连续谱背景之间的大的干扰效应的影响，这往往会过度补偿任何共振贡献。一个可靠的建模所产生的顶对不变的质量形状需要包括高阶QCD校正，这是在这里。这些非线性光学校正的计算是准确的，在所有的贡献，但在类的非factorisable两个回路图，其中包括在一个近似的方式，使所有的红外奇异限制被保存。我们提出了几个基准点与重希格斯质量在700 $-3000 $ GeV的范围内考虑生产稳定的顶夸克的数值结果。我们发现，干涉效应占主导地位的BSM信号产生尖锐的倾角结构，而不是共振峰。对LHC运行2、运行3和HL-LHC探索了BSM效应的显著性和可排除性。
We present a next-to-leading-order (NLO) study of the process $pp \; ( \to \{ h_1, h_2 \}) \to t\bar{t} + X$ in the 1-Higgs-singlet extension of the Standard Model with an additional heavy Higgs boson $h_2$ that mixes with the light Higgs boson $h_1$. This process is subject to large interference effects between loop-induced Higgs-mediated amplitudes and the QCD continuum background which tend to overcompensate any resonance contributions. A reliable modelling of the resulting top-pair invariant mass shapes requires the inclusion of higher-order QCD corrections, which are presented here. The computation of these NLO corrections is exact in all contributions but in the class of non-factorisable two-loop diagrams which are included in an approximate way such that all infrared singular limits are preserved. We present numerical results for several benchmark points with heavy Higgs masses in the range $700$--$3000$ GeV considering the production of stable top quarks. We find that the interference effects dominate the BSM signal yielding sharp dip structures instead of resonance peaks. The significance and excludability of the BSM effect is explored for the LHC Run 2, Run 3 and HL-LHC.