Search for exotic leptons in final states with two or three leptons and fat-jets at 13 TeV LHC
Institute of Physics, Bhubaneswar（布巴内斯瓦尔物理研究所）；Homi Bhabha National Institute（霍米·巴巴国立研究所）；Department of Physics and Astrophysics, University of Delhi（德里大学物理与天体物理学系）
本文探讨了在13 TeV LHC中通过两个或三个轻子及一个或两个肥jets的最终状态探测质量超过1 TeV的奇异轻子，提出并研究了有效的搜索策略。
摘要：
在大型规范多重集中的奇异轻子，出现在许多超出标准模型（SM）的场景中，可以在LHC中成对或关联产生。由于其大质量，最终衰变产物——SM轻子和玻色子——往往具有高度的Boost，来自SM玻色子的喷注更可能表现为单个肥喷注而不是两个分离的喷注。相应的SM背景被抑制，最终状态包含两个或三个轻子及一个或两个肥喷注的最终状态预计对探测质量超过1 TeV的奇异费米子敏感，我们提出并研究了适当的研究策略。为了聚焦本质，我们考虑了SM的扩展，通过单一类型的轻子多重集（三重集、四重集或五重集）进行扩展，考虑到这些简化模型通常作为更雄心勃勃的场景的低能极限，以解决SM的各种缺陷。在13 TeV LHC上系统且全面地研究了九种此类场景，我们发现相应的5σ发现范围从985 GeV到1650 GeV（1345 GeV到2020 GeV）对于300（3000）fb$^{-1}$。
英文摘要：
Exotic leptons in large gauge multiplets, appearing in many scenarios beyond the Standard Model (SM), can be produced at the LHC in pairs or association. Owing to their large masses, their eventual decay products -- SM leptons and bosons -- tend to be highly boosted, with the jets stemming from the SM bosons more likely to manifest themselves as a single fat-jet rather than two resolved ones. With the corresponding SM backgrounds being suppressed, final states with two or three leptons and one or two fat-jets are expected to be sensitive in probing exotic fermions much heavier than 1 TeV, and we propose and investigate an appropriate search strategy. To concentrate on the essential, we consider extensions of the SM by leptonic multiplets of a single kind (triplets, quadruplets or quintuplets), bearing in mind that such simplified models typically arise as low-energy limits of more ambitious scenarios addressing various lacunae of the SM. Performing a systematic and comprehensive study of nine such scenarios at the 13 TeV LHC, we find that the corresponding $5σ$ discovery reaches a range from 985 GeV to 1650 GeV (1345 GeV to 2020 GeV) for 300 (3000) fb$^{-1}$.
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Institute of Physics, Bhubaneswar（布巴内斯瓦尔物理研究所）；Department of Physics, SGTB Khalsa College（SGTB卡尔萨学院物理系）；Department of Physics and Astrophysics, University of Delhi（德里大学物理与天体物理学系）；Homi Bhabha National Institute（霍米·巴巴国立研究所）
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