论文标题
超轻斧头暗物质及其解决方案的宇宙学张力
Cosmological Tension of Ultralight Axion Dark Matter and its Solutions
论文作者
论文摘要
许多提出的和正在进行的实验搜索轴线暗物质，其质量接近小规模结构（$ {\ cal o}（10 ^{ - 21}} {\ rm ev}）$）。我们考虑了这些模型的晚期宇宙宇宙学，表明要求轴是具有与冷暗物质相匹配的物质功率谱的频谱将轴突耦合的大小限制为可见扇区。将这些限制与当前和未来的实验努力进行比较，我们发现许多搜索需要与标准模型场异常大的耦合轴，与早期宇宙中的斧子的填充方式无关。我们调查可以减轻界限的机制，即引入大电荷，各种形式的动力学混合，发条结构以及施加离散对称性。我们为每种情况提供一个明确的模型，并探索它们的现象学和生存能力，以产生可检测到的超轻斧头暗物质。
A number of proposed and ongoing experiments search for axion dark matter with a mass nearing the limit set by small scale structure (${\cal O} ( 10 ^{ - 21 } {\rm eV} ) $). We consider the late universe cosmology of these models, showing that requiring the axion to have a matter-power spectrum that matches that of cold dark matter constrains the magnitude of the axion couplings to the visible sector. Comparing these limits to current and future experimental efforts, we find that many searches require axions with an abnormally large coupling to Standard Model fields, independently of how the axion was populated in the early universe. We survey mechanisms that can alleviate the bounds, namely, the introduction of large charges, various forms of kinetic mixing, a clockwork structure, and imposing a discrete symmetry. We provide an explicit model for each case and explore their phenomenology and viability to produce detectable ultralight axion dark matter.
