arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1110.3045astro-ph.CO
收藏

相互作用的暗能量宇宙学中的聚集和红移空间扭曲

Clustering and redshift-space distortions in interacting dark energy cosmologies

Federico Marulli, Marco Baldi, Lauro Moscardini

摘要:

我们在耦合暗能量(cDE)宇宙学的框架下研究宇宙大尺度结构(LSS)的空间性质。使用公共晕目录从CoDECS模拟-最大的一套N体实验,迄今为止这样的宇宙学场景-我们估计冷暗物质(CDM)晕的聚类和偏置函数,无论是在真实的和红移空间。此外,我们调查的暗能量(DE)耦合的几何和动力学红移空间扭曲的影响,量化的差异相对于协调LambdaCDM模型。在z~0处,即使为了与最新的宇宙微波背景(CMB)数据相一致而对cDE模型进行了散射归一化处理,其CDM晕的空间性质也与LambdaCDM非常相似。在较高的红移,我们发现,DE耦合产生了显着的规模依赖的抑制晕集群和偏置功能。这种效应强烈依赖于耦合强度,在尺度r<5-10 Mpc/h时不退化为σ 8。此外,我们发现,耦合DE强烈影响的线性失真参数,β,和成对的奇特的速度色散,sigma 12。虽然在这项工作中考虑的模型被认为是所有与目前可用的观测数据一致,下一代的星系调查将能够把强大的约束DE和CDM利用红移空间聚类各向异性的形状之间的耦合水平。

英文摘要:

We investigate the spatial properties of the large scale structure (LSS) of the Universe in the framework of coupled dark energy (cDE) cosmologies. Using the public halo catalogues from the CoDECS simulations -- the largest set of N-body experiments to date for such cosmological scenarios -- we estimate the clustering and bias functions of cold dark matter (CDM) haloes, both in real- and redshift-space. Moreover, we investigate the effects of the dark energy (DE) coupling on the geometric and dynamic redshift-space distortions, quantifying the difference with respect to the concordance LambdaCDM model. At z~0, the spatial properties of CDM haloes in cDE models appear very similar to the LambdaCDM case, even if the cDE models are normalized at last scattering in order to be consistent with the latest Cosmic Microwave Background (CMB) data. At higher redshifts, we find that the DE coupling produces a significant scale-dependent suppression of the halo clustering and bias function. This effect, that strongly depends on the coupling strength, is not degenerate with sigma8 at scales r<5-10 Mpc/h. Moreover, we find that the coupled DE strongly affects both the linear distortion parameter, beta, and the pairwise peculiar velocity dispersion, sigma12. Although the models considered in this work are found to be all in agreement with presently available observational data, the next generation of galaxy surveys will be able to put strong constraints on the level of coupling between DE and CDM exploiting the shape of redshift-space clustering anisotropies.

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。

↑