论文标题
关于腐烂的冷暗物质的更新限制
Updated constraints on decaying cold dark matter
论文作者
论文摘要
在本文中，我们更新了以深色辐射（DR）为衰减产品的简单衰减冷暗物质（DCDM）模型的约束。我们考虑了生命周期的两个不同的制度，即短暂且长寿，并使用Planck（2018）的最新CMB数据推断出对衰减参数的新约束，我们比较了我们比较以前的Planck数据（2015）推断出的约束。我们特此表明，最新的CMB数据限制了长期寿命中的DCDM的分数两倍，从而导致我们当前的最佳2 $σ$上限为$ f _ {\ rm dcdm} <2.44 \％\％$ $。在短暂的制度中，与先前的CMB数据相比，我们获得了$ f _ {\ rm dcdm} <13.1 \％$的略带宽松的2 $σ$上限。如果我们包括来自Boss DR-12的Baryonic声学振荡数据，则分别在$ f _ {\ rm dcdm} <2.62 \％$和$ f _ {\ rm dcdm dcdm dcdm} <1.49 <1.49 <1.49 \％$中，长寿和短暂的制度在$ f _ {\ rm dcdm} <2.62 \％$和$ f _ {\ rm dcdm} <2.62 \％$和$ f _ {\ rm dcdm} <％\％$中都会放松。我们还研究了该模型如何影响哈勃和$σ_8$张力，我们发现每个衰减方案都可以稍微缓解不同的紧张局势。因此，该模型不能一次应对两个紧张局势，并且每个紧张局面的改进并不重要。此外，我们通过彻底分析短寿命DCDM对辐射密度的影响并得出短寿命DCDM和校正之间的映射，即$ΔN_ {\ rm eff} $，对有效数量的无质量中微子物种来改善先前的工作。
In this paper we update the constraints on the simple decaying cold dark matter (DCDM) model with dark radiation (DR) as decay product. We consider two different regimes of the lifetime, i.e. short-lived and long-lived, and use the most recent CMB data from Planck (2018) to infer new constraints on the decay parameters with which we compare the constraints inferred by the previous Planck data (2015). We hereby show that the newest CMB data constrains the fractional amount of DCDM twice as much as the previous data in the long-lived regime, leading to our current best 2$σ$ upper bound of $f_{\rm dcdm}<2.44\%$. In the short-lived regime, we get a slightly looser 2$σ$ upper bound of $f_{\rm dcdm}<13.1\%$ compared to the previous CMB data. If we include Baryonic Acoustic Oscillations data from BOSS DR-12, the constraints in both the long-lived and the short-lived regimes relax to $f_{\rm dcdm}<2.62\%$ and $f_{\rm dcdm}<1.49\%$, respectively. We also investigate how this model impacts the Hubble and $σ_8$ tensions, and we find that each of the decay regimes can slightly relieve a different one of the tensions. The model can thus not accommodate both tensions at once, and the improvements on each are not significant. We furthermore improve on previous work by thoroughly analysing the impacts of short-lived DCDM on the radiation density and deriving a mapping between short-lived DCDM and a correction, $ΔN_{\rm eff}$, to the effective number of massless neutrino species.
