论文标题
用群集边缘作为标准尺子测量宇宙学距离
Measuring Cosmological Distances Using Cluster Edges as a Standard Ruler
论文作者
论文摘要
星系簇的视线速度分散曲线表现出与轨道星系空间范围相对应的“扭结”。由于簇的空间范围与速度分散谱的幅度相关，因此我们可以将此特征用作重力校准的标准标准器。具体而言，速度分散数据的幅度使我们能够推断物理簇的大小。因此，可以将轮廓中“纠结”角度尺度的观测转换为群集的距离测量。假设可以通过模拟校准群集半径与群集速度分散的关系，我们预测，通过Sloan Digital Sky Survey（SDSS）的现有数据，我们将能够以$ 3 \％$ $ precision来衡量哈勃常数。通过来自暗能量光谱仪器（DESI）的数据实施我们的方法将导致$ 1.3 \％$ $的测量哈勃常数。添加宇宙学超新星数据将DESI测量的不确定性提高到$ 0.7 \％$。
The line-of-sight velocity dispersion profile of galaxy clusters exhibits a "kink" corresponding to the spatial extent of orbiting galaxies. Because the spatial extent of a cluster is correlated with the amplitude of the velocity dispersion profile, we can utilise this feature as a gravity-calibrated standard ruler. Specifically, the amplitude of the velocity dispersion data allows us to infer the physical cluster size. Consequently, observations of the angular scale of the "kink" in the profile can be translated into a distance measurement to the cluster. Assuming the relation between cluster radius and cluster velocity dispersion can be calibrated from simulations, we forecast that with existing data from the Sloan Digital Sky Survey (SDSS) we will be able to measure the Hubble constant with $3\%$ precision. Implementing our method with data from the Dark Energy Spectroscopic Instrument (DESI) will result in a $1.3\%$ measurement of the Hubble constant. Adding cosmological supernova data improves the uncertainty of the DESI measurement to $0.7\%$.
