发表机构
D. V. Skobeltsyn Institute of Nuclear Physics, M. V. Lomonosov Moscow State University; Marietta Blau Institute (MBI) for Particle Physics; Joint Institute for Nuclear Research; Faculty of Physics, University of Vienna（莫斯科国立大学 D.V. 斯科别尔钦核物理研究所; 玛丽埃塔·布劳粒子物理研究所; 联合核研究所; 维也纳大学物理学院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过分析$B\to K^* M_X$和$B_s\to \phi M_X$衰变，检验Belle II超出事件的暗物质起源，区分标量与矢量介体情景，并给出预期事件数。
AI 中文摘要
最近，我们已表明，Belle II在$B\to K M_X$衰变中观测到的超出事件具有暗物质（DM）起源的假设能够成功描述数据。在具有标量（S情景）或矢量（V情景）介体的两种暗物质情景中，通过拟合$B\to K M_X$数据，暗物质参数（质量和耦合）已以相当小的不确定性被提取出来。相同的机制导致$B_s\to (\eta,\eta',\phi) M_X$衰变率出现类似的增强。我们对$B\to K^* M_X$和$B_s\to \phi M_X$衰变进行了详细分析，并表明这些衰变为S和V情景提供了清晰的探针：与标准模型相比，在S情景中预期增强约1.6倍，而V情景则导致约3.5倍的更大增强。对于$B\to K^* M_X$衰变，我们提供了Belle II在已报告$B\to K M_X$衰变相对于标准模型预期有相当大增强的样本中的预期事件数。
英文摘要
Recently, we have shown that the hypothesis of the dark-matter (DM) origin of the Belle II excess events in $B\to K M_X$ decays allows for a successful description of the data. The DM parameters (masses and couplings) in two DM scenarios with either scalar (S-scenario) or vector (V-scenario) mediator have been extracted with rather small uncertainty from fits to the $B\to K M_X$ data. The same mechanism leads to a similar enhancement of the $B_s\to (η,η',ϕ) M_X$ decay rates. We present a detailed analysis of $B\to K^* M_X$ and $B_s\to ϕM_X$ decays and show that these decays provide a clear probe of the S- and V-scenarios: Compared to the Standard Model, in the S-scenario an enhancement by a factor $\sim 1.6$ is expected, whereas the V-scenario leads to a much larger enhancement by a factor $\sim 3.5$. For the $B\to K^* M_X$ decays, we provide the expected number of events at Belle II for the sample for which a rather large enhancement of $B\to K M_X$ decays compared to the Standard Model expectations has been reported.
Comments11 pages
