发表机构
Institute for Theoretical Physics, Kanazawa University; Faculty of Education, Miyazaki University（金泽大学理论物理研究所; 宫崎大学教育学部）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
该研究提出通过观测SHiP实验中暗标量玻色子的双介子、三介子等衰变模式，利用事例数比值及互补衰变道，探测GeV尺度暗标量领域的CP破坏。
AI 中文摘要
我们研究GeV尺度暗标量玻色子衰变为介子、缪子和光子过程中的CP破坏，考虑其与标准模型费米子的标量及赝标量耦合，以探究如何通过衰变过程探测暗标量玻色子的CP结构。标量相互作用主要诱导双介子末态衰变，赝标量相互作用则主要诱导三介子末态衰变。我们提出同时观测这两类衰变模式，作为探测暗标量领域CP破坏的手段。基于重介子衰变产生暗标量的机制，我们评估了SHiP和FASER2实验的预期信号事例率。研究发现，对于GeV尺度附近的暗标量质量，SHiP实验中三介子与双介子衰变事例数的比值，有潜力探测大范围的CP破坏参数空间；此外，双缪子和双光子衰变道可为CP破坏搜寻提供互补信息。
英文摘要
We investigate CP violation in the decays of a GeV-scale dark scalar boson into mesons, muons and photons. Both scalar and pseudoscalar couplings to the SM fermions are considered to study how the CP structure of the dark scalar boson can be probed through its decays. The scalar and pseudoscalar interactions predominantly induce decays into two-meson and three-meson final states, respectively. We propose the simultaneous observation of these two classes of decay modes as a probe of CP violation in the dark scalar sector. The expected signal rates at the SHiP and FASER2 experiments are evaluated based on the dark scalar production from heavy-meson decays. We find that the ratio of three-meson to two-meson decay events at SHiP has the potential to probe a wide range of the CP-violating parameter space for dark scalar masses around the GeV scale. We also show that the two-muon and di-photon channels can provide complementary information for the CP violation search.
Comments31 pages, 13 figures
