Our main aim in this paper is to present detailed studies to probe the top quark flavor changing neutral current (FCNC) interactions at tqg, tqγ, tqH and $tqZ({\sigma }^{\mu \nu },{\gamma }_{\mu })$ vertices in the triple-top signal $pp\to t\overline{t}t(\overline{t}t\overline{t})$ at the high energy proposal of Large Hadron Collider (HE-LHC) and future circular hadron-hadron collider (FCC-hh). To this end, we investigate the production of three top quarks which arises from the FCNC couplings taken into account the fast simulation at $\sqrt{s}=27$ TeV of HE-LHC and 100 TeV of FCC-hh considering the integrated luminosities of 10, 15 and 20 ab⁻¹. All the relevant backgrounds are considered in a cut based analysis to obtain the limits on the anomalous couplings and the corresponding branching ratios. The obtained exclusion limits on the coupling strengths and the branching ratios are summarized and compared in detail with the results in the literature, namely the most recent direct LHC experimental limits and HL-LHC projections as well. We show that, for the higher energy phase of LHC, a dedicated search for the top quark FCNC couplings can achieve much better sensitivities to the triple-top signal than other top quark production scenarios. We found that the limits for the branching ratios of tqg and tqH transitions could reach an impressive sensitivity and the obtained 95% CL limits are at least three orders of magnitude better than the current LHC experimental results as well as the existing projections of HL-LHC.

本文的主要目的是提供详细的研究，以探究tqg，tqγ，tqH和tqH处的顶级夸克风味变化中性电流（FCNC）相互作用。$Ťqž（{\sigma }^{\mu \nu }，{\gamma }_{\mu }）$ 三重顶信号中的顶点 $pp\to Ť\overline{Ť}Ť（\overline{Ť}Ť\overline{Ť}）$大型强子对撞机（HE-LHC）和未来的圆形强子-强子对撞机（FCC-hh）的高能提案。为此，我们考虑了FCNC联轴器产生的三个顶夸克的产生，并考虑了$\sqrt{s}=27$考虑到10、15和20 ab ^-1的综合发光度，HE-LHC的TeV和FCC-hh的100 TeV 。在基于剪切的分析中考虑所有相关背景，以获取异常耦合和相应分支比的限制。总结了获得的关于耦合强度和支化比的极限，并与文献中的结果进行了详细的比较，即最近的直接LHC实验极限以及HL-LHC预测。我们表明，对于大型强子对撞机的较高能量阶段，专用搜索顶夸克FCNC联轴器比其他顶夸克生产方案对三重顶信号的灵敏度更高。我们发现tqg和tqH的分支比的极限 过渡可能会达到令人印象深刻的灵敏度，并且获得的95％CL限至少比当前LHC实验结果以及HL-LHC的现有预测好三个数量级。