论文标题
Hubble用GW190521作为偏心黑洞合并的Hubble常量测量
Hubble Constant Measurement with GW190521 as an Eccentric Black Hole Merger
论文作者
论文摘要
引力波观测可用于准确测量哈勃常数$ H_0 $，并可以帮助理解IA Supernovae类型的约束与宇宙微波背景之间的当前差异。中子星合并主要用于此目的，因为它们的电磁发射可用于大大减少测量不确定性。在这里，我们使用最近观察到的黑洞合并GW190521及其候选电磁对应物估算$ H_0 $，ZTF使用了对GW190521的性质的高度偏心说明。我们发现，GW190521的重建距离和候选宿主星系的红移与我们偏心模型的标准宇宙学更一致，而不是我们重建没有偏心率的源参数。我们获得$ h_0 = 88.6^{+17.1} _ { - 34.3} $ \，km \，s $^{ - 1} $ mpc $^{ - 1} $ for GW190521，并且$ h_0 = 73.4^{+6.9} _ { - 10.7} $ \，km \，s $^{ - 1} $ mpc $^{ - 1} $与中子星级合并GW170817的结果结合使用。我们的结果表明，使用黑洞合并的未来$ H_0 $计算将需要考虑可能的偏心率。对于极端情况，AGN磁盘中二进制的轨道速度可以代表一个严重的系统不确定性。
Gravitational wave observations can be used to accurately measure the Hubble constant $H_0$ and could help understand the present discrepancy between constraints from Type Ia supernovae and the cosmic microwave background. Neutron star mergers are primarily used for this purpose as their electromagnetic emission can be used to greatly reduce measurement uncertainties. Here we estimate $H_0$ using the recently observed black hole merger GW190521 and its candidate electromagnetic counterpart found by ZTF using a highly eccentric explanation of the properties of GW190521. We find that the reconstructed distance of GW190521 and the redshift of the candidate host galaxy are more consistent with standard cosmology for our eccentric model than if we reconstruct the source parameters assuming no eccentricity. We obtain $H_0=88.6^{+17.1}_{-34.3}$\,km\,s$^{-1}$Mpc$^{-1}$ for GW190521, and $H_0=73.4^{+6.9}_{-10.7}$\,km\,s$^{-1}$Mpc$^{-1}$ in combination with the results of the neutron star merger GW170817. Our results indicate that future $H_0$ computations using black hole mergers will need to account for possible eccentricity. For extreme cases, the orbital velocity of binaries in AGN disks can represent a significant systematic uncertainty.
