论文标题
映射宇宙扩展:通过单个二进制中子合并检测启用哈勃常数的百分比测量值
Mapping the Universe Expansion: Enabling percent-level measurements of the Hubble Constant with a single binary neutron-star merger detection
论文作者
论文摘要
来自二进制中子星级合并GW170817的引力波和电磁信号的联合观察允许对哈勃常数$ H_0 $进行新的独立测量,尽管不确定性约为15 \%,在1 $σ$。使用未来检测器网络对类似来源的观察将允许更精确的测量值$ H_0 $。然而,这些目前在很大程度上受到亮度距离与重力波信号中源倾斜度之间的固有堕落性的限制。我们表明,重力波中的高阶模式可用于在中子星合并的灵感和合并后阶段中分解天体物理参数估计中的这种堕落性。我们表明,对于类似于GW170817的距离的系统,此方法可在单个检测中实现$ H_0 $的百分比测量值。这将允许研究$ H_0 $的时间变化和空间各向异性,并具有前所未有的精度。我们研究了不同的网络配置如何影响$ H_0 $的测量结果,并讨论了科学驱动因素对拟议的2.5和第三代重力波检测器的含义。最后,我们表明,用这些未来观测值测量的$ H_0 $的精度仅受电磁对应物的红移测量而受到限制。
The joint observation of the gravitational-wave and electromagnetic signal from the binary neutron-star merger GW170817 allowed for a new independent measurement of the Hubble constant $H_0$, albeit with an uncertainty of about 15\% at 1$σ$. Observations of similar sources with a network of future detectors will allow for more precise measurements of $H_0$. These, however, are currently largely limited by the intrinsic degeneracy between the luminosity distance and the inclination of the source in the gravitational-wave signal. We show that the higher-order modes in gravitational waves can be used to break this degeneracy in astrophysical parameter estimation in both the inspiral and post-merger phases of a neutron star merger. We show that for systems at distances similar to GW170817, this method enables percent-level measurements of $H_0$ with a single detection. This would permit the study of time variations and spatial anisotropies of $H_0$ with unprecedented precision. We investigate how different network configurations affect measurements of $H_0$, and discuss the implications in terms of science drivers for the proposed 2.5- and third-generation gravitational-wave detectors. Finally, we show that the precision of $H_0$ measured with these future observatories will be solely limited by redshift measurements of electromagnetic counterparts.