发表机构
Indian Institute of Technology Gandhinagar; Homi Bhabha National Institute（印度理工学院古吉拉特分校; 霍米·巴巴国立研究所）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究提出标准模型的$\mathbb{Z}_3$对称复标量暗物质扩展，引入矢量型夸克和轻子，通过单圈分析结合味、精确、暗物质及对撞机约束，确定质量下限并展示HL-LHC的探测潜力。
AI 中文摘要
我们研究了标准模型的一种最小扩展，该扩展包含一个由$\mathbb{Z}_3$对称性稳定的复标量暗物质（CSDM）候选粒子、一个下型矢量型夸克（VLQ）和一个带电矢量型轻子（VLL）。额外的矢量型费米子不仅使CSDM能够通过半湮灭和协同湮灭过程在希格斯共振区域之外重现观测到的遗迹丰度，而且还诱导了味物理、电弱精确、暗物质和对撞机观测量之间的关联信号。我们对中性介子混合、稀有介子衰变、带电轻子味破坏、带电轻子反常磁矩以及$Z$极点观测量进行了全面的单圈分析。我们发现，中性介子混合和稀有介子衰变对VLQ部分提供了主要约束，而带电轻子味破坏过程则强烈限制了VLL的汤川耦合。当前的直接探测限制要求，对于TeV量级的VLQ质量，希格斯-暗物质耦合$\lambda_{\Phi H} \lesssim 5\times10^{-3}$且VLQ汤川耦合$\mathtt{y}_d \lesssim 0.05$，而目前的间接探测搜索没有施加额外限制。综合所有味物理、电弱精确、暗物质和对撞机约束，我们确定了可行的参数区域，其中CSDM质量大约高于$1.0~\rm TeV$，VLQ质量大约高于$1.5~\rm TeV$。我们还发现，LHC可以在$2\sigma$置信水平上排除质量高达约$1.6~(0.38)$ TeV的VLQ（VLL），具体取决于CSDM质量。HL-LHC可以进一步探测参数空间的扩展区域，在$3\sigma$水平上具有发现前景。最后，我们展示了味物理、暗物质和对撞机搜索在探测这一框架中的互补性。
英文摘要
We investigate a minimal extension of the SM consisting of a $\mathbb{Z}_3$-stabilized complex scalar dark matter (CSDM) candidate, a down-type vector-like quark (VLQ), and a charged vector-like lepton (VLL). The additional vector-like fermions not only enable the CSDM to reproduce the observed relic abundance beyond the Higgs-resonance region through semi-annihilation and co-annihilation processes, but also induce correlated signatures across flavor, electroweak precision, dark matter, and collider observables. We perform a comprehensive one-loop analysis of neutral meson mixing, rare meson decays, charged lepton flavor violation, anomalous magnetic moments of charged leptons, and $Z$-pole observables. We find that neutral meson mixing and rare meson decays provide the dominant constraints on the VLQ sector, while charged lepton flavor-violating processes strongly restrict the VLL Yukawa couplings. Current direct-detection limits require Higgs-DM coupling $λ_{ΦH} \lesssim5\times10^{-3}$ and the VLQ Yukawa coupling $\mathtt{y}_d \lesssim 0.05$ for TeV-scale VLQ masses, whereas present indirect-detection searches impose no additional constraints. Combining all flavor, electroweak precision, dark matter, and collider constraints, we identify viable parameter regions with CSDM masses above approximately $1.0~\rm TeV$ and VLQ masses above about $1.5~\rm TeV$. We also find that the LHC can exclude VLQs (VLLs) with masses up to approximately $1.6~(0.38)$ TeV, depending on the CSDM mass, at the $2σ$ confidence level. The HL-LHC can further probe an extended region of the parameter space, with discovery prospects at the $3σ$ level. Finally, we demonstrate the complementarity of flavor, dark matter, and collider searches in probing this framework.
Comments77 pages, 28 figures
