论文标题
$ t \ bar t tϕ $生产中角变量的标量质量依赖性
Scalar mass dependence of angular variables in $t\bar tϕ$ production
论文作者
论文摘要
在本文中，我们在LHC上使用通用的标量玻色子（$ ϕ $）探讨了Top-Quark对（$ t \ bar {t} $）的相关生产中的CP歧视。我们使用$ t \ bar {t} ϕ $系统的dialeptonic最终状态，探索CP-EVIN（$ ϕ = H $）或CP-ODD（$ ϕ = a $）的几种可观察到的CP-敏感性（$ ϕ = H $）或CP-odd（$ ϕ = H $）（$ ϕ = a $），带有$ t \ bar {t} ϕ $系统的最终状态，$ t {t}。我们表明，对于此频道中几百GEV的$ ϕ $玻色子块，CP-searches几乎是不可能的。使用MADGRAPH5 MC@NLO产生的标准模型背景和信号事件进行了完整的现象学分析，并使用运动学拟合重建。最敏感的CP观察物用于计算置信度（CLS）作为光度的函数，用于排除具有标量和伪内分玻色子质量的不同信号假设，其范围从$ = 40 GEV到200 GEV，范围从$ M_D $ = 40 GEV到200 GEV。我们通过分析CP侵略角度在复杂的两-higgs Doublet模型的参数空间中的测量（或极限）的影响来最终确定。
In this paper we explore CP discrimination in the associated production of top-quark pairs ($t\bar{t}$) with a generic scalar boson ($ϕ$) at the LHC. We probe the CP-sensitivity of several observables for a varying scalar boson mass and CP-number, either CP-even ($ϕ=H$) or CP-odd ($ϕ=A$), using dileptonic final states of the $t\bar{t}ϕ$ system, with $ϕ\rightarrow b\bar{b}$. We show that CP-searches are virtually impossible for $ϕ$ boson masses above a few hundred GeV in this channel. A full phenomenological analysis was performed, using Standard Model background and signal events generated with MadGraph5 MC@NLO and reconstructed using a kinematic fit. The most sensitive CP-observables are used to compute Confidence Levels (CLs), as a function of luminosity, for the exclusion of different signal hypotheses with scalar and pseudoscalar boson masses that range from $m_ϕ$ = 40 GeV up to 200 GeV. We finalize by analysing the impact of a measurement (or limit) of the CP-violating angle in the parameter space of a complex two-Higgs doublet model known as the C2HDM.
