A Hubble constant measurement from superluminal motion of the jet in GW170817
A Hubble constant measurement from superluminal motion of the jet in GW170817
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DOI：
10.1038/s41550-019-0820-1
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发表时间：
2018-06
期刊：
影响因子：
14.1
通讯作者：
K. Hotokezaka;E. Nakar;O. Gottlieb;S. Nissanke;K. Masuda;G. Hallinan;K. Mooley;A. Deller
中科院分区：
文献类型：
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作者：
K. Hotokezaka;E. Nakar;O. Gottlieb;S. Nissanke;K. Masuda;G. Hallinan;K. Mooley;A. Deller
哈勃常数（H 0）测量宇宙当前的膨胀率，在宇宙学中起着重要作用。在过去的几十年里，人们付出了巨大的努力来测量H 0（参考文献，, , , , , , , -).引力波（GW）源伴随着电磁（EM）对应物提供了H 0的独立标准警报测量（参考文献，- ），正如发现中子星星合并，GW 170817（参考文献，-).这种测量并不假设宇宙学模型，也不依赖于宇宙距离阶梯。来自GW 170817的GW信号及其EM定位的第一次联合分析导致测量（中位数和对称68%可信区间）。在此分析中，GW信号中的源距离和观测角度之间的简并主导了H 0测量不确定性。最近，已经获得了对使用GW 170817的无线电对应物的高角分辨率成像的观察角度的严格约束。在这里，我们报告了一个改进的measurementby使用这些新的无线电观测，结合以前的GW和EM数据。我们估计，与没有此类数据的50-100 GW事件相比，另外15个具有无线电图像和光变曲线数据的GW 170817事件将可能解决普朗克和造父变星超新星测量之间的紧张关系。
The Hubble constant (H0) measures the current expansion rate of the Universe, and plays a fundamental role in cosmology. Tremendous effort has been dedicated over the past decades to measureH0(refs., , , , , , , , –). Gravitational wave (GW) sources accompanied by electromagnetic (EM) counterparts offer an independent standard siren measurement ofH0(refs., –), as demonstrated following the discovery of the neutron star merger, GW170817 (refs., –). This measurement does not assume a cosmological model and is independent of a cosmic distance ladder. The first joint analysis of the GW signal from GW170817 and its EM localization led to a measurement of(median and symmetric 68% credible interval). In this analysis, the degeneracy in the GW signal between the source distance and the observing angle dominated theH0measurement uncertainty. Recently, tight constraints on the observing angle using high angular resolution imaging of the radio counterpart of GW170817 have been obtained. Here, we report an improved measurementby using these new radio observations, combined with the previous GW and EM data. We estimate that 15 more GW170817-like events, having radio images and light curve data, as compared with 50–100 GW events without such data,, will potentially resolve the tension between the Planck and Cepheid–supernova measurements.