论文标题
$ h_ {0} $和$σ_{8} $ tensions的互动暗物质和深色辐射的模型
A Model of Interacting Dark Matter and Dark Radiation for $H_{0}$ and $σ_{8}$ Tensions
论文作者
论文摘要
我们提出了一个描述暗区（DS）的模型，其特征是两个相互作用保持有效的效率，直到重组后的物质主导时代的后期：暗辐射（DR）之间的相互作用以及一小部分暗物质和深色辐射之间的相互作用。黑暗扇区由（1）主要的成分冷碰撞DM（DM1），（2）亚占主导地位的冷DM（DM2）和（3）自我相互作用DR。当确保足够数量的DR并与DR相互作用的DM2相互作用的总DM密度的几％时，已知该设置能够同时解决哈勃和$σ_{8} $张力。鉴于此，我们提出了一种在逻辑上是自然的场景，具有一个有趣的理论结构，其中一个隐藏的不间断的量规组$ {\ rm su}（5）_ {\ rm x} \ otimes {\ rm u}（\ rm u}（1）_ {\ rm x} $。我们的黑暗部门模型不会引入任何新的标量场，而仅包含紫外线（UV）制度中的无质手性费米子和量规场。因此，它基于由$ {\ rm su}（5）_ {\ rm x} $的强度限制引起的新量表（DM2质量，$ m _ {\ rm dm2} $）。 DM2-DR和DR-DR交互都归因于$ {\ rm U}（1）_ {\ rm x} $的相同长距离交互。我们表明，当我们的模型以$ g _ {\ rm x} = \ Mathcal {o}（10^{ - 3}）为特征时，我们的模型可以解决宇宙张力。 DM2} = \ Mathcal {O}（1） - \ MathCal {O}（100）{\ rm Gev} $和$ t _ {\ rm DS}/t _ {\ rm sm} {\ rm sm} \ simeq0.3-0.3-0.3-0.3-0.3-0.4 $ g _ $ g _ $ g _ \ is $ rm xuge u}（1）_ {\ rm x} $和$ t _ {\ rm ds} $（$ t _ {\ rm sm} $）是DS（标准模型扇区）的温度。我们的模型解释了DM2和DR的候选者，并且DM1可以是任何类型的CDM。
We present a model describing the dark sector (DS) featured by two interactions remaining efficient until late times in the matter-dominated era after recombination: the interaction among dark radiations (DR), and the interaction between a small fraction of dark matter and dark radiation. The dark sector consists of (1) a dominant component cold collisionless DM (DM1), (2) a sub-dominant cold DM (DM2) and (3) a self-interacting DR. When a sufficient amount of DR is ensured and a few percent of the total DM density is contributed by DM2 interacting with DR, this set-up is known to be able to resolve both the Hubble and $σ_{8}$ tension. In light of this, we propose a scenario which is logically natural and has an intriguing theoretical structure with a hidden unbroken gauge group ${\rm SU}(5)_{\rm X}\otimes {\rm U}(1)_{\rm X}$. Our model of the dark sector does not introduce any new scalar field, but contains only massless chiral fermions and gauge fields in the ultraviolet (UV) regime. As such, it introduces a new scale (DM2 mass, $m_{\rm DM2}$) based on the confinement resulting from the strong dynamics of ${\rm SU}(5)_{\rm X}$. Both DM2-DR and DR-DR interactions are attributed to an identical long range interaction of ${\rm U}(1)_{\rm X}$. We show that our model can address the cosmological tensions when it is characterized by $g_{\rm X}=\mathcal{O}(10^{-3})-\mathcal{O}(10^{-2})$, $m_{\rm DM2}=\mathcal{O}(1)-\mathcal{O}(100){\rm GeV}$ and $T_{\rm DS}/T_{\rm SM}\simeq0.3-0.4$ where $g_{\rm X}$ is the gauge coupling of ${\rm U}(1)_{\rm X}$ and $T_{\rm DS}$ ($T_{\rm SM}$) is a temperature of the DS (Standard Model sector). Our model explains candidates of DM2 and DR, and DM1 can be any kind of CDM.
