We investigate the potential of the HL-LHC for discovering new physics effects via the same-sign top pair signatures. We focus on the semileptonic (electron and muon) decay of the top quarks and study the reach for a simplified model approach where top quark flavor changing could occur through a neutral scalar exchange. A relatively smaller background contribution and clean signature are the advantages of the leptonic decay mode of the same-sign bosons in the same-sign production processes of top quark pairs. Assuming the FCNC between top quark, up-type quark, and scalar boson from the new physics interactions, the branchings could be excluded of the order . We use angular observables of the same-sign lepton pairs and the top quark kinematics in the process which provide the possibility of separation of new physics signal from the SM backgrounds using machine-learning techniques. We find that the same-sign top quark pair production is quite capable of testing the top-Higgs FCNCs at the HL-LHC.

中文翻译：

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通过 HL-LHC 上的 Top-Higgs FCNC 相互作用研究同号顶对产生

我们研究了 HL-LHC 通过同符号顶对签名发现新物理效应的潜力。我们专注于顶夸克的半轻子（电子和 μ 介子）衰变，并研究简化模型方法的范围，其中顶夸克味的变化可能通过中性标量交换发生。相对较小的背景贡献和干净的特征是顶夸克对同号产生过程中同号玻色子的轻子衰变模式的优势。假设来自新物理相互作用的顶夸克、上型夸克和标量玻色子之间的 FCNC，分支可以被排除在阶外。我们在此过程中使用同号轻子对的角观测值和顶夸克运动学，这提供了使用机器学习技术从 SM 背景中分离新物理信号的可能性。我们发现同号顶夸克对的产生完全能够测试 HL-LHC 的顶希格斯 FCNC。