AI 中文总结
研究利用 DAMIC - M 探测器约 1.3 kg - 天数据，通过分析低能电子反冲空间扩散特征，给出太阳反射暗物质在重介质和超轻介质基准下暗物质 - 电子散射截面 90%置信水平上限，探测了相关参数空间。
AI 中文摘要
太阳是一个天然的暗物质加速器。在太阳等离子体中散射的星系晕粒子出现时的速度远超银河系逃逸速度，提供了增强通量，将直接探测实验的运动学范围扩展到亚 MeV 质量范围。我们使用在莫达讷地下实验室用硅跳变电荷耦合器件（CCDs）获取的约 1.3 kg - 天的数据，给出了来自 DAMIC - M 原型探测器对太阳反射暗物质（SRDM）的约束。利用低能电子反冲的空间扩散特征，我们得出了重介质和超轻介质基准下暗物质 - 电子散射截面的 90%置信水平上限，在 0.1 MeV 时达到$\bar{\sigma}_e\sim 3.16 \cdot 10^{-37} \rm{cm^2}$。对于超轻介质，我们的限制与通过约 1.3 kg - 天的积分曝光获得的世界领先限制具有竞争力。这些结果探测了恒星冷却界限和标准晕搜索的地面限制之间的参数空间，这是仅依赖标准晕通量的直接探测实验无法到达的区域。
英文摘要
The Sun acts as a natural dark matter accelerator. Galactic halo particles scattering in the solar plasma emerge with velocities well beyond the Galactic escape speed, providing a boosted flux that extends the kinematic reach of direct detection experiments into the sub-MeV mass regime. We present constraints on solar-reflected dark matter (SRDM) from the DAMIC-M prototype detector using $\sim$1.3~kg-day of data acquired with silicon skipper charge coupled devices (CCDs) at the Modane Underground Laboratory. Exploiting the spatial diffusion signature of low-energy electron recoils, we derive 90% C.L. upper limits on the DM-electron scattering cross section for both heavy- and ultralight-mediator benchmarks, reaching $\barσ_e\sim 3.16 \cdot 10^{-37} \rm{cm^2}$ at $0.1$ MeV. For the ultralight mediator, our limits are competitive with the world-leading constraints, achieved with an integrated exposure of $\sim1.3$~kg-day. These results probe the parameter space between stellar-cooling bounds and terrestrial limits from standard halo searches, a region inaccessible to direct detection experiments relying solely on the standard halo flux.
