arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1809.10045astro-ph.CO
收藏

大质量星系团回溅的弱透镜约束

Weak lensing constraints on splashback around massive clusters

O. Contigiani, H. Hoekstra, Y. M. Bahé

摘要:

回溅半径$r_\text{sp}$区分了大质量暗物质晕周围坍缩和下落物质的物理状态。在宇宙学模拟中,这个位置与球形平均密度分布$ρ(r)$的陡峭化有关。在这项工作中,我们测量的溅回功能的堆积弱引力透镜信号的$27$大质量星系团的集群加拿大比较项目与仔细控制的残余系统学的影响。我们发现,沿视线的额外结构的存在下引入的剪切显着影响噪声在大集群中心的距离。虽然我们没有检测到一个显着的陡峭,使用一个简单的参数模型,使我们能够测量$r_\text{sp}=3.5^{+1.1}_{-0.7}$共动Mpc和对数斜率$γ= \log ρ/ \log r$在这一点上,$γ(r_\text{sp}) = -4.3^{+1.0}_{-1.5}$的值。

英文摘要:

The splashback radius $r_\text{sp}$ separates the physical regimes of collapsed and infalling material around massive dark matter haloes. In cosmological simulations, this location is associated with a steepening of the spherically averaged density profile $ρ(r)$. In this work, we measure the splashback feature in the stacked weak gravitational lensing signal of $27$ massive clusters from the Cluster Canadian Comparison Project with careful control of residual systematics effects. We find that the shear introduced by the presence of additional structure along the line of sight significantly affects the noise at large clustercentric distances. Although we do not detect a significant steepening, the use of a simple parametric model enables us to measure both $r_\text{sp}=3.5^{+1.1}_{-0.7}$ comoving Mpc and the value of the logarithmic slope $γ= \log ρ/ \log r$ at this point, $γ(r_\text{sp}) = -4.3^{+1.0}_{-1.5}$.

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。

↑