发表机构
Liaoning Normal University; Universidade Federal Fluminense; Presidency University; Durban University of Technology（辽宁师范大学; 弗鲁米嫩塞联邦大学; 总统大学; 德班理工大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过最新宇宙学数据约束暗物质-暗能量相互作用模型，发现仅部分情景支持相互作用，但贝叶斯证据仍偏好ΛCDM，且对S8参数影响轻微。
AI 中文摘要
我们重新审视了一个相互作用的暗物质（DM）—暗能量（DE）模型，其特征是相互作用函数 $Q = \Gamma \rho_x$，其中 $\Gamma$ 是常数耦合参数，$\rho_x$ 是暗能量的能量密度。这种类型的相互作用不依赖于哈勃率或其他外部参数，而仅依赖于暗能量的基本属性，如其状态方程（EoS）$w_x$。我们特别关注 $w_x$，并研究了由 $w_x$ 的性质区分的三种不同相互作用情景，即 $w_x = -1$（当暗能量对应于真空能量时）、$w_x < -1$（当暗能量具有幻影行为时）和 $w_x > -1$（精质暗能量）。我们使用最新的宇宙学数据集对所有情景进行了约束，包括来自Planck 2018的CMB、来自DESI DR2的BAO，以及三个SNIa汇编（PantheonPlus、Union3和DESY5）。我们的分析揭示，当所有三个数据集组合时，在 $w_x = -1$ 和 $w_x < -1$ 的情景中支持相互作用的证据，但从贝叶斯证据分析来看，$\Lambda$CDM仍然比这些相互作用情景更受青睐。关于 $S_8$ 参数，当 $w_x > -1$ 时，这种相互作用情景在所有数据集中导致略低的估计值。
英文摘要
We revisit an interacting dark matter (DM) -- dark energy (DE) model characterized by the interaction function $Q = Γρ_x$, where $Γ$ is a constant coupling parameter and $ρ_x$ is the energy density of DE. This type of interaction is independent of the Hubble rate or other external parameters, but depends only on the fundamental properties of DE, such as its equation of state (EoS), $w_x$. We pay special attention to $w_x$ and study three distinct interacting scenarios distinguished by the nature of $w_x$, i.e. $w_x =-1$ (when DE corresponds to the vacuum energy), $w_{x} < -1$ (when DE has a phantom behavior), and $w_x > -1$ (quintessential DE). We constrain all of them using the most recent cosmological datasets, including CMB from Planck 2018, BAO from DESI DR2, and three compilations of SNIa (PantheonPlus, Union3, and DES-Dovekie). Our analyses reveal that evidence of interaction is supported in scenarios with $w_x =-1$ and $w_x < -1$ when all three datasets are combined, but from the Bayesian evidence analysis, $Λ$CDM remains favored over these interacting scenarios. Regarding the $S_8$ parameter, when $w_x > -1$, this interacting scenario leads to mildly lower estimates across all datasets.
CommentsVersion corresponding to the published article; incorporates corrections made during proof production. 25 pages, 20 figures
Journal refPhys. Rev. D 114, 063549 (2026)
