Multi-messenger Observations of a Binary Neutron Star Merger
Multi-messenger Observations of a Binary Neutron Star Merger
复制标题
双中子星合并的多信使观测
DOI：
10.3847/2041-8213/aa91c9
复制
发表时间：
2017-10-20
影响因子：
7.9
通讯作者：
Woudt, P. A.
中科院分区：
文献类型：
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作者：
Abbott, B. P.;Abbott, R.;Woudt, P. A.
2017年8月17日，高级LIGO和高级处女座探测器通过引力波观测到了一颗合并时间为12：41：04的双中子星合并候选星(后来命名为GW170817)。费米伽马射线暴监视器独立探测到一次伽马射线暴(GRB170817A)，相对于合并时间，时间延迟为∼1.7 S。根据引力波信号，震源最初定位在31°2的天空区域，光度距离为40−8+8Mpc，分量质量与中子星一致。成分质量后来被测量到在0.86到2.26M⊙的范围内。在一米两半球(1M2H)团队使用1米天文望远镜合并不到11小时后，在电磁频谱上发起了广泛的观测活动，导致在NGC4993(在∼40MPC)中发现了明亮的光学瞬变(SSS17a，现在国际宇航联合会鉴定为AT 2017gfo)。多个团队在一小时内独立探测到了这种光学瞬变现象。随后的观察针对的是该物体及其环境。早期的紫外线观测显示了一个蓝色的瞬变，在48小时内就消失了。光学和红外观测显示，∼在10天内向红移。在早期未被探测到之后，在合并16天后，在瞬变者的位置∼9和∼分别发现了X射线和无线电发射。X射线和射电辐射都可能来自一个与产生紫外线/光学/近红外辐射的物理过程不同的物理过程。在后续搜索中，没有发现超高能伽马射线，也没有发现与来源一致的候选中微子。这些观测支持这样的假设，即GW170817是由NGC 4993中的两颗中子星合并而成，随后是一次短暂的伽马射线暴(GRB 170817A)和一颗由喷出物中合成的r-过程核的放射性衰变提供动力的千诺诺瓦/马克诺瓦。
On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ∼ 1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40 − 8 + 8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 M ⊙ . An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ∼ 40 Mpc ) less than 11 hours after the merger by the One-Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ∼10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ∼ 9 and ∼ 16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC 4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta.