AI 中文总结
该研究利用量子层析构建对顶夸克耦合CP破坏敏感的最优可观测量，通过模拟在LHC和FCC-ee上实现了优于传统方法的新物理能标探测灵敏度。
AI 中文摘要
量子层析程序可从正负电子对撞机和强子对撞机的双轻子角关联中重建顶夸克对的完整自旋密度矩阵。我们利用对称性论证识别对顶夸克耦合中CP破坏敏感的层析可观测量。作为具体示例，我们研究这些可观测量对大型强子对撞机（LHC）和未来环形正负电子对撞机（FCC-ee）中（色）电偶极矩算符的敏感性。我们还构建了最优可观测量，其结合层析信息和运动学信息，为每个算符及产生过程实现统计最优灵敏度。该分析基于对顶夸克对产生及双轻子道衰变的快速探测器模拟。我们预测，在FCC-ee（质心系能量365 GeV，积分亮度3 ab⁻¹）上，电弱电偶极矩对新物理能标（偶极耦合的倒数）的95%置信水平灵敏度为10-15 TeV；在LHC Run 2（高亮度LHC即HL-LHC）上，顶夸克色电偶极矩的灵敏度分别为40 TeV和200 TeV。这些灵敏度超过了当前实验用于这些算符的传统可观测量的灵敏度，表明层析方法在搜索CP破坏方面具有强大能力。
英文摘要
Quantum tomography program reconstructs the full spin density matrix of top-quark pairs from dilepton angular correlations at both electron-positron and hadron colliders. We use symmetry arguments to identify tomographic observables sensitive to CP violation in top quark couplings. As a concrete example, we study the sensitivity of these observables to (chromo-)electric dipole moment operators at the LHC and the FCC-ee. We also construct the optimal observable, which combines tomographic and kinematic information to achieve statistically optimal sensitivity for each operator and production process. The analysis is based on fast detector simulation of top pair production and decay in the dilepton channel. We project a $95\%$ CL sensitivity to new-physics scales (the inverse dipole couplings) of $10-15$ TeV for the electroweak electric dipoles at the FCC-ee ($365$ GeV, $3~{\rm ab}^{-1}$) and of 40 (200) TeV for the top chromo-electric dipole moment at the LHC Run 2 (HL-LHC). This sensitivities exceed those of the traditional observables currently used by experiments to use for these operators, indicating the power of the tomographic approach to search for CP violation.
Comments41 pages, 9 figures
