arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1507.07586astro-ph.COhep-ph
收藏

Planck 2015宇宙微波背景各向异性角功率谱对早期和晚期积分Sachs-Wolfe效应的约束

Constraints on the Early and Late Integrated Sachs-Wolfe effects from Planck 2015 Cosmic Microwave Background Anisotropies angular power spectra

Giovanni Cabass, Martina Gerbino, Elena Giusarma, Alessandro Melchiorri, Luca Pagano, Laura Salvati

摘要:

综合Sachs-Wolfe(ISW)效应预言了当宇宙膨胀不受物质支配时,由于引力势随时间的变化,在宇宙微波背景中会产生额外的各向异性。因此,在早期宇宙中,由于相对论粒子在复合时的存在,以及在宇宙晚期,当暗能量开始主导膨胀时,ISW效应是可以预期的。与标准图像的偏差可以通过$A_{e\text{ISW}}$和$A_{l\text{ISW}}$参数化,这两个参数重新调整了早期和晚期ISW效应的总体幅度。分析Planck 2015发布的最新CMB温度谱,我们检测到早期ISW的存在,$A_{e\mathrm{ISW}} = 1.06\pm0.04$在68% CL时具有高度显著性,$A_{l\mathrm{ISW}} < 1.1$的晚期ISW上限为95% CL。包括最近的极化数据从普朗克实验结果在$A_{e\mathrm{ISW}} = 0.999\pm0.028$在68% CL,在更好的协议值$A_{e\mathrm{ISW}} = 1$的标准宇宙学。考虑到最近从CMB温度各向异性和弱透镜效应之间的相关性中检测到的晚期ISW,预测$A_{l\mathrm{ISW}}=0.85\pm0.21$值为68% CL,显示出$4σ$证据。我们讨论的情况下,我们的结果的稳定性的额外的相对论性的能量成分的有效中微子数$N_\mathrm{eff}$和CMB透镜振幅$A_\mathrm{L}$的参数。

英文摘要:

The Integrated Sachs-Wolfe (ISW) effect predicts additional anisotropies in the Cosmic Microwave Background due to time variation of the gravitational potential when the expansion of the universe is not matter dominated. The ISW effect is therefore expected in the early universe, due to the presence of relativistic particles at recombination, and in the late universe, when dark energy starts to dominate the expansion. Deviations from the standard picture can be parameterized by $A_{e\text{ISW}}$ and $A_{l\text{ISW}}$, which rescale the overall amplitude of the early and late ISW effects. Analyzing the most recent CMB temperature spectra from the Planck 2015 release, we detect the presence of the early ISW at high significance with $A_{e\mathrm{ISW}} = 1.06\pm0.04$ at 68% CL and an upper limit for the late ISW of $A_{l\mathrm{ISW}} < 1.1$ at 95% CL. The inclusion of the recent polarization data from the Planck experiment results in $A_{e\mathrm{ISW}} = 0.999\pm0.028$ at 68% CL, in better agreement with the value $A_{e\mathrm{ISW}} = 1$ of a standard cosmology. When considering the recent detections of the late ISW coming from correlations between CMB temperature anisotropies and weak lensing, a value of $A_{l\mathrm{ISW}}=0.85\pm0.21$ is predicted at 68% CL, showing a $4σ$ evidence. We discuss the stability of our result in the case of an extra relativistic energy component parametrized by the effective neutrino number $N_\mathrm{eff}$ and of a CMB lensing amplitude $A_\mathrm{L}$.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑