arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1803.03091hep-phastro-ph.CO
收藏

21厘米处有暗物质的迹象？

Signs of Dark Matter at 21-cm?

Rennan Barkana, Nadav Joseph Outmezguine, Diego Redigolo, Tomer Volansky

备注：
Constraints updated, typos corrected. Conclusions unchanged
发表信息：
Phys. Rev. D 98, 103005 (2018)
阅读 PDF
arXiv 页面 ↗HTML 原文 ↗

摘要：

最近，EDGES合作报告了$z=17$周围天空平均21厘米光谱中的异常吸收信号。这样的信号可以被理解为在所谓的宇宙黎明时代期间或之前氢气意外冷却的指示。在这里，我们探讨的可能性，暗物质冷却气体通过速度依赖，卢瑟福式的相互作用。我们认为，这种相互作用需要一个光介质，这是高度限制第五力实验和恒星冷却的限制。因此，原则上只有一个隐藏的或可见的光子才能传递这样的力。因此，中性氢起着次要的主导作用，并且冷却通过残余的自由电子和质子发生。我们发现，这两个方案是强烈的约束所预测的暗物质自相互作用和限制的毫荷电暗物质分别。我们的结论是，21厘米的吸收线是不太可能的气体冷却的结果，通过散射的主要成分的暗物质。一个1\%的子组件的millicharged暗物质仍然是一个可行的解释。

英文摘要：

Recently the EDGES collaboration reported an anomalous absorption signal in the sky-averaged 21-cm spectrum around $z=17$. Such a signal may be understood as an indication for an unexpected cooling of the hydrogen gas during or prior to the so called Cosmic Dawn era. Here we explore the possibility that dark matter cooled the gas through velocity-dependent, Rutherford-like interactions. We argue that such interactions require a light mediator that is highly constrained by 5th force experiments and limits from stellar cooling. Consequently, only a hidden or the visible photon can in principle mediate such a force. Neutral hydrogen thus plays a sub-leading role and the cooling occurs via the residual free electrons and protons. We find that these two scenarios are strongly constrained by the predicted dark matter self-interactions and by limits on millicharged dark matter respectively. We conclude that the 21-cm absorption line is unlikely to be the result of gas cooling via the scattering with a dominant component of the dark matter. An order 1\% subcomponent of millicharged dark matter remains a viable explanation.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

↑