论文标题
重新审视宇宙加速的时代
Revisiting the epoch of cosmic acceleration
论文作者
论文摘要
我们重新审视宇宙加速的时期，其特征是从减速到加速相的过渡的红移。此红移称为过渡红移（$ z_t $）。我们使用最常见的$λ$ CDM和XCDM型号的空间平坦和非平板变体来对过渡红移和其他模型参数一起构成约束。该分析的数据来自最近和更新的万神殿+超新星数据集以及从宇宙天文序列获得的哈勃参数测量值。我们考虑两个数据集及其各自的协方差矩阵，结合了各种统计和系统的不确定性。我们观察到，使用H（Z）和SNE的组合数据集，过渡红移的最佳拟合价值在于所有四个暗能量模型的$ 0.61 <Z_T <0.82 $。顺便说一句，我们观察到非平板模型的正曲率以及几个模型参数之间的相关性。
We revisit the epoch of cosmic speed-up characterized by the redshift of transition from a decelerated to an accelerated phase. This redshift is termed the transition redshift ($z_t$). We use the spatially Flat and Non-Flat variants of the most common $Λ$CDM and XCDM models to put constraints on the transition redshift along with the other model parameters. The data for this analysis comes from the recent and updated Pantheon+ Supernova dataset and the Hubble parameter measurements obtained from Cosmic Chronometers. We consider both datasets with their respective covariance matrices incorporating all kinds of statistical and systematic uncertainties. We observe that using the combined datasets of H(z) and SNe, the best fit value of transition redshift lies in the range $0.61 < z_t < 0.82$ for all four dark energy models. Incidentally, we observe a positive curvature for the Non-Flat models and correlations between several model parameters.
