Search for t t ¯ resonances in the lepton plus jets final state with ATLAS using 4.7 fb - 1 of p p collisions at s = 7 TeV
Search for t t ¯ resonances in the lepton plus jets final state with ATLAS using 4.7 fb - 1 of p p collisions at s = 7 TeV
复制标题
使用 ATLAS 使用 s = 7 TeV 处的 4.7 fb - 1 次 p p 碰撞搜索轻子加射流最终状态中的 t t 共振
DOI：
10.1103/physrevd.88.012004
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发表时间：
2013
影响因子：
5
通讯作者：
Aad G
中科院分区：
文献类型：
--
作者：
Aad G
在大型强子对撞机的ATLAS实验中，使用在质心能量处收集的质子-质子()碰撞数据的积分光度来搜索衰变为顶级夸克对()的新粒子。在衰变中，使用了轻子加喷注的末态，其中一个玻色子轻子衰变，另一个强子衰变。该系统采用小半径和大半径两种喷注方式进行重建，后者辅以喷射子结构分析。在不变质谱图中，搜索与标准模型期望值相比的数据事件数量的局部过剩。没有发现共振的证据，并且在两个基准模型中预测的大规模状态确定了95%的可信度水平的生产率限制。窄共振的截面乘以分支比的上限从5.1pB(对于0.5TeV的玻色子质量)到0.03pb(对于3TeV的质量)。不包括质量低于1.74TeV的狭义疏水拓扑色共振。还推导出了宽色八位组共振的极限。对于低于2.07 TeV的质量，排除了Randall-Sundrum模型中胶子的Kaluza-Klein激发。
A search for new particles that decay into top quark pairs () is performed with the ATLAS experiment at the LHC using an integrated luminosity ofof proton–proton () collision data collected at a center-of-mass energy. In thedecay, the lepton plus jets final state is used, where oneboson decays leptonically and the other hadronically. Thesystem is reconstructed using both small-radius and large-radius jets, the latter being supplemented by a jet substructure analysis. A search for local excesses in the number of data events compared to the Standard Model expectation in theinvariant mass spectrum is performed. No evidence for aresonance is found and 95% credibility-level limits on the production rate are determined for massive states predicted in two benchmark models. The upper limits on the cross section times branching ratio of a narrowresonance range from 5.1 pb for a boson mass of 0.5 TeV to 0.03 pb for a mass of 3 TeV. A narrow leptophobic topcolorresonance with a mass below 1.74 TeV is excluded. Limits are also derived for a broad color-octet resonance with. A Kaluza–Klein excitation of the gluon in a Randall–Sundrum model is excluded for masses below 2.07 TeV.