Dark photon portal dark matter with the 21-cm anomaly
Dark photon portal dark matter with the 21-cm anomaly
复制标题
DOI：
10.1140/epjc/s10052-019-6542-9
复制
发表时间：
2018-04
期刊：
影响因子：
--
通讯作者：
Lian-Bao Jia
中科院分区：
文献类型：
--
作者：
Lian-Bao Jia
EDGES合作报告了一个强吸收剖面，这表明氢气比预期的要冷。这可能是正常物质和暗物质（DM）之间的非引力相互作用的特征，一种可能的解释是，一小部分带电荷的DM与正常物质散射在一起，DM的质量在几十MeV左右。为了获得小比例的荷电DM，同时又能容忍约束条件，本文对暗光子入口标量和矢量荷电DM进行了探索。我们认为暗光子的质量略高于带电DM质量的两倍，因此在冻结期，带电DM主要以p波湮灭，在共振附近湮灭增强。暗光子主要衰变成带电的DM，轻子碰撞实验允许暗光子与SM粒子的耦合。导出了相应的参数空间。未来的轻子碰撞实验可以通过产生不可见的暗光子来寻找带电的DM。
A strong absorption profile was reported by the EDGES Collaboration, which indicates the hydrogen gas being colder than expected. It could be signatures of non-gravitational interactions between normal matter and dark matter (DM), and a possible explanation is that a small fraction of millicharged DM scatters with normal matter, with the DM mass in tens of MeV. To obtain the small fraction of millicharged DM and meanwhile being tolerant as regards the constraints, the dark photon portal scalar and vector millicharged DM are explored in this paper. We consider the mass of dark photon to be slightly above twice the millicharged DM mass, and thus the millicharged DM predominantly annihilates in p-wave during the freeze-out period, with the annihilation being enhanced near the resonance. The dark photon mainly decays into millicharged DM, and couplings of the dark photon with SM particles could be allowed by the lepton collision experiments. The corresponding parameter spaces are derived. Future lepton collision experiments can be employed to search for millicharged DM via the production of the invisible dark photon.