论文标题
相变的质量变化
Mass-varying Dark Matter from a Phase Transition
论文作者
论文摘要
我们提出了一个质量变化的暗物质（MVDM）模型，该模型由标量场和通过简单的Yukawa耦合相互作用的费米管场组成，并包含标量场的指数自我相互作用潜力。分析了这种耦合标量特性系统在不断扩展的宇宙中的演变，我们发现它最初的行为类似于辐射，但随后经历了相位过渡，之后它的行为类似于无压力的暗物质。该模型的一个自由参数是相变的温度。由费米的质量给出的暗物质粒子的质量是从此得出的。对于10 meV至$ 10^7 $ GEV之间的相变温度，当前的暗物质遗物密度是在1 GEV到$ 10^9 $ GEV范围内达到的。在这个暗物质模型中，标量成为暗物质的亚占主导地位的成分，可以将结构形成的幅度降低多达几个百分比。另一个特征是，假设LCDM从早期和延迟探针推断出的当前暗物质密度约为10％的当前暗物质密度的差异测量。
We propose a mass-varying dark matter (MVDM) model consisting of a scalar field and a fermionic field interacting via a simple Yukawa coupling, and containing an exponential self-interaction potential for the scalar field. Analyzing the evolution of this coupled scalar-fermion system in an expanding Universe, we find that it initially behaves like radiation but then undergoes a phase transition after which it behaves like pressureless dark matter. The one free parameter of this model is the temperature at which the phase transition occurs; the mass of the dark matter particle, given by the mass of the fermion, is derived from this. For a phase transition temperature between 10 MeV and $10^7$ GeV, the current dark matter relic density is achieved for a fermion mass in the range of 1 GeV to $10^9$ GeV. In this dark matter model, the scalar becomes a sub-dominant unclustered component of dark matter that can lower the amplitude of structure formation by up to a few percent. Another feature is that the mass-varying fermion component can lead to discrepant measurements of the current dark matter density of about ten percent inferred from early and late-time probes assuming LCDM.
