发表机构
Southeastern Universities Research Association (SURA); NASA Goddard Space Flight Center; International Institute of Physics, Federal University of Rio Grande do Norte; Observatório Nacional（东南大学研究协会; 美国国家航空航天局戈达德太空飞行中心; 北里奥格兰德联邦大学物理国际研究所; 国家天文台）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文提出重暗物质内热上散射解释 LZ 高能核反冲候选事件，并指出其辐射衰变产生亚 MeV 伽马射线线，可被 COSI 探测，为验证该解释提供机会。
AI 中文摘要
重暗物质的内热上散射为 LUX-ZEPLIN (LZ) 最近报告的高能核反冲候选事件提供了一种引人注目的解释，其特征反冲能量 $E_R \propto \delta$，其中 $\delta$ 是暗物质态之间的质量劈裂。宇宙学和实验约束促使原始较重态被耗尽，而该态可以在银河系晕中重新生成。我们表明，如果较重态以辐射方式衰变，相同的质量劈裂决定了伽马射线线的能量，即 $E_\gamma \simeq \delta$。对于我们的基准模型，这导致一条亚 MeV 线，位于康普顿光谱仪和成像仪 (COSI) 的预期探测范围内，该仪器计划于 2027 年发射。因此，LZ 候选事件作为暗物质信号的确认将促使专门搜索亚 MeV 伽马射线线，而 COSI 为检验这一解释提供了及时的机会。
英文摘要
Endothermic upscattering of heavy dark matter offers a compelling interpretation of the high-energy nuclear-recoil candidate recently reported by LUX-ZEPLIN (LZ), with a characteristic recoil energy $E_R \propto δ$, where $δ$ is the mass splitting between the dark matter states. Cosmological and experimental constraints motivate the depletion of the primordial heavier state, which can be regenerated in the Galactic halo. We show that, if the heavier state decays radiatively, the same mass splitting sets the energy of a gamma-ray line, $E_γ\simeq δ$. For our benchmark, this leads to a sub-MeV line within the projected reach of the Compton Spectrometer and Imager (COSI), scheduled for launch in 2027. The confirmation of the LZ candidate event as a dark matter signal would therefore motivate dedicated searches for sub-MeV gamma-ray lines, with COSI providing a timely opportunity to test this interpretation.
Comments7 pages, 4 figures. Comments are welcome!
