Search for resonant t t-bar production in lepton+jets events in pp collisions at sqrt(s)=7 TeV
Search for resonant t t-bar production in lepton+jets events in pp collisions at sqrt(s)=7 TeV
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DOI：
10.1007/jhep12(2012)015
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发表时间：
2012-09
影响因子：
5.4
通讯作者：
Cms Collaboration
中科院分区：
文献类型：
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作者：
Cms Collaboration
提出了一种与模型无关的对重共振衰变成顶-反顶夸克对的产生的研究。该搜索基于包含一个轻子（μ子或电子）和至少两个射流的事件，这些射流选自数据样本，对应于在 TeV 的 pp 碰撞中收集的 4.4-5.0 fb−1 的积分光度。结果是针对提高产量和阈值产量而优化的两个专门搜索的组合。没有观察到超出标准模型过程的预期产量的事件。对于低于 1.49 (2.04) TeV 的质量，具有窄（宽）宽度的 Topcolor Z' 玻色子在 95% 置信水平下被排除，并且对于高于 1 TeV 的共振质量，在生产截面乘以分支分数上设置 0.3 (1.3) pb 或更低的上限。 Randall-Sundrum 模型中质量低于 1.82 TeV（置信水平为 95%）的胶子的 Kaluza-Klein 激发也被排除，并且对于高于 1 TeV 的共振质量，产生截面乘以分支分数的上限设置为 0.7 pb 或更低。
A model-independent search for the production of heavy resonances decaying into top-antitop quark pairs is presented. The search is based on events containing one lepton (muon or electron) and at least two jets selected from data samples corresponding to an integrated luminosity of 4.4-5.0 fb− 1 collected in pp collisions atTeV. Results are presented from the combination of two dedicated searches optimized for boosted production and production at threshold. No excess of events is observed over the expected yield from the standard model processes. Topcolor Z′ bosons with narrow (wide) width are excluded at 95% confidence level for masses below 1.49 (2.04) TeV and an upper limit of 0.3 (1.3) pb or lower is set on the production cross section times branching fraction for resonance masses above 1 TeV. Kaluza-Klein excitations of a gluon with masses below 1.82 TeV (at 95% confidence level) in the Randall-Sundrum model are also excluded, and an upper limit of 0.7 pb or lower is set on the production cross section times branching fraction for resonance masses above 1 TeV.