论文标题
使用Atlas 13 TEV $ PP $碰撞数据的Spin-0暗物质介体和无形的希格斯的限制，带有两个顶级夸克，在最终状态下缺少横向动量
Constraints on spin-0 dark matter mediators and invisible Higgs decays using ATLAS 13 TeV $pp$ collision data with two top quarks and missing transverse momentum in the final state
论文作者
论文摘要
本文介绍了针对最终状态的搜索统计组合，其特征是存在零，一个或两个lept子的存在，至少是一个源自$ b $ quark和缺失的横向动量的喷气机。分析是在LHC $ pp $碰撞中直接生产暗物质的标准模型之外的现象，使用139 fb $^{ - \ text {1}} $与Atlas detector收集的数据以13 TEV的中心能量收集。结果是用具有Spin-0标量或伪级介体粒子的简化暗物质模型来解释的。此外，结果是根据希格斯玻色子看不见的分支比的上限来解释的，其中希格斯玻色子是根据标准模型与一对顶夸克相关的标准模型产生的。对于标量（伪尺度）暗物质模型，所有耦合都设置为统一，统计组合将最佳单个通道排除的质量范围扩展到50（25）GEV，不包括高达370 GEV的调解员群体。此外，假设标量（伪cal）介体质量为10 GEV，统计组合将预期的耦合排除率提高了14％（24％）。在95％的置信度下，观察到Higgs Boson隐形分支比率为0.38（0.30 $^{+\ text {0.13}} _ { - \ text {0.09}} $）。
This paper presents a statistical combination of searches targeting final states with two top quarks and invisible particles, characterised by the presence of zero, one or two leptons, at least one jet originating from a $b$-quark and missing transverse momentum. The analyses are searches for phenomena beyond the Standard Model consistent with the direct production of dark matter in $pp$ collisions at the LHC, using 139 fb$^{-\text{1}}$ of data collected with the ATLAS detector at a centre-of-mass energy of 13 TeV. The results are interpreted in terms of simplified dark matter models with a spin-0 scalar or pseudoscalar mediator particle. In addition, the results are interpreted in terms of upper limits on the Higgs boson invisible branching ratio, where the Higgs boson is produced according to the Standard Model in association with a pair of top quarks. For scalar (pseudoscalar) dark matter models, with all couplings set to unity, the statistical combination extends the mass range excluded by the best of the individual channels by 50 (25) GeV, excluding mediator masses up to 370 GeV. In addition, the statistical combination improves the expected coupling exclusion reach by 14% (24%), assuming a scalar (pseudoscalar) mediator mass of 10 GeV. An upper limit on the Higgs boson invisible branching ratio of 0.38 (0.30$^{+\text{0.13}}_{-\text{0.09}}$) is observed (expected) at 95% confidence level.
