"Figure 9c" of "Search for supersymmetry in proton-proton collisions at 13 TeV using identified top quarks"

CERN-LHC. CMS. A search for supersymmetry is presented based on proton-proton collision events containing identified hadronically decaying top quarks, no leptons, and an imbalance pT_miss in transverse momentum. The data were collected with the CMS detector at the CERN LHC at a center-of-mass energy of 13 TeV, and correspond to an integrated luminosity of 35.9 fb−1. Search regions are defined in terms of the multiplicity of bottom quark jet and top quark candidates, the pT_miss, the scalar sum of jet transverse momenta, and the mT2 mass variable. No statistically significant excess of events is observed relative to the expectation from the standard model. Lower limits on the masses of supersymmetric particles are determined at 95% confidence level in the context of simplified models with top quark production. For a model with direct top squark pair production followed by the decay of each top squark to a top quark and a neutralino, top squark masses up to 1020 GeV and neutralino masses up to 430 GeV are excluded. For a model with pair production of gluinos followed by the decay of each gluino to a top quark-antiquark pair and a neutralino, gluino masses up to 2040 GeV and neutralino masses up to 1150 GeV are excluded. These limits extend previous results.

欧洲核子研究中心大型强子对撞机（CERN-LHC）紧凑型缪子线圈（CMS）实验：本研究基于包含已识别强衰变顶夸克、无轻子且存在横向动量缺失（pT_miss）的质子-质子碰撞事例，开展超对称（supersymmetry）搜寻分析。实验数据由CERN LHC上的CMS探测器采集，质心系能量为13 TeV，对应积分亮度为35.9 fb⁻¹。搜寻区域的定义基于底夸克喷注与顶夸克候选事例的多重数、横向动量缺失（pT_miss）、喷注横向动量标量和以及mT2质量变量。与标准模型的理论预期相比，未观测到具有统计显著性的事例超出。基于顶夸克产生的简化模型框架，在95%置信度下给出了超对称粒子质量的下限。对于直接顶超夸克（top squark）成对产生，且每个顶超夸克衰变至一个顶夸克与中性微子（neutralino）的模型，可排除质量不超过1020 GeV的顶超夸克与质量不超过430 GeV的中性微子。对于胶微子（gluino）成对产生，且每个胶微子衰变至一个顶夸克-反顶夸克对与中性微子的模型，可排除质量不超过2040 GeV的胶微子与质量不超过1150 GeV的中性微子。上述结果拓展了此前的研究结论。