"Figure 6-e" of "Search for heavy Higgs bosons decaying to a top quark pair in proton-proton collisions at $\sqrt{s} =$ 13 TeV"

A search is presented for additional scalar (H) or pseudoscalar (A) Higgs bosons decaying to a top quark pair in proton-proton collisions at a center-of-mass energy of 13 TeV. The data set analyzed corresponds to an integrated luminosity of 35.9 fb-1 collected by the CMS experiment at the LHC. Final states with one or two charged leptons are considered. The invariant mass of the reconstructed top quark pair system and variables that are sensitive to the spin of the particles decaying into the top quark pair are used to search for signatures of the H or A bosons. The interference with the standard model top quark pair background is taken into account. A moderate signal-like deviation compatible with an A boson with a mass of 400 GeV is observed with a global significance of 1.9 standard deviations. New stringent constraints are reported on the strength of the coupling of the hypothetical bosons to the top quark, with the mass of the bosons ranging from 400 to 750 GeV and their total relative width from 0.5 to 25%. The results of the search are also interpreted in a minimal supersymmetric standard model scenario. Values of m_A from 400 to 700 GeV are probed, and a region with values of tan(beta) below 1.0 to 1.5, depending on m_A, is excluded at 95% confidence level.

本文报告了一项搜寻研究：在质心系能量为13 TeV的质子-质子对撞中，寻找衰变至顶夸克（top quark）对的额外标量（H）或赝标量（A）希格斯玻色子。本次分析使用的数据集，对应大型强子对撞机（Large Hadron Collider，LHC）上的CMS实验采集的35.9 fb⁻¹积分亮度。研究考虑包含一个或两个带电轻子（charged lepton）的末态。通过重建顶夸克对系统的不变质量（invariant mass），以及对衰变至顶夸克对的粒子自旋敏感的各类变量，来搜寻H或A玻色子的信号特征。本分析计入了与标准模型（Standard Model）顶夸克对本底的干涉效应。观测到一处与质量为400 GeV的A玻色子相容的类信号偏离，其全局显著性为1.9倍标准偏差。针对假想玻色子与顶夸克的耦合强度，本研究给出了新的严格约束：玻色子质量区间为400 GeV至750 GeV，总相对宽度区间为0.5%至25%。本搜寻结果还在最小超对称标准模型（Minimal Supersymmetric Standard Model）框架下进行了诠释。本次研究探测了m_A为400 GeV至700 GeV的区间，并在依赖于m_A的tanβ低于1.0至1.5的区域，以95%置信水平排除了该类参数空间。