Multimessenger tests of the weak equivalence principle from GW170817 and its electromagnetic counterparts
Multimessenger tests of the weak equivalence principle from GW170817 and its electromagnetic counterparts
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GW170817 及其电磁对应物弱等效原理的多信使测试
DOI：
10.1088/1475-7516/2017/11/035
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发表时间：
2017
影响因子：
6.4
通讯作者：
Zhu Zong-Hong
中科院分区：
文献类型：
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作者：
Wei Jun-Jie;Zhang Bin-Bin;Wu Xue-Feng;Gao He;Meszaros Peter;Zhang Bing;Dai Zi-Gao;Zhang Shuang-Nan;Zhu Zong-Hong
引力波（GW）事件GW170817与邻近星系NGC 4933内双中子星并合的电磁（EM）信号（如短伽马射线暴SGRB 170817A或宏新星）的同时探测为弱等效原理（WEP）提供了一种新的多信使测试，扩展了用GWs和光子进行的WEP测试。假设来自GW170817的GW信号与来自SGRB 170817A或宏观新星的光子之间的到达时间延迟主要归因于银河系的引力势，我们证明了GW170817/宏观新星与WEP偏差的严格上限为Δγ< 1.4× 10−3，GW170817/SGRB 170817A的偏差为Δγ< 5.9× 10−8。当我们考虑室女座星系团的引力势而不是银河系的引力时，GW170817/SGRB 170817A的WEP精度可以得到更严格的约束（~ 0.9× 10−10）。通过两种不同粒子γ参数的相对差异变化，这为WEP提供了迄今为止最严格的限制。与其他多信使（光子和中微子）结果相比，我们的极限比超新星1987A的中微子和光子所给出的极限严格了7个数量级，几乎与与grb和耀变体耀斑相关的低显著性中微子所得到的极限一样好或提高了6个数量级。
The coincident detection of a gravitational-wave (GW) event GW170817 with electromagnetic (EM) signals (eg, a short gamma-ray burst SGRB 170817A or a macronova) from a binary neutron star merger within the nearby galaxy NGC 4933 provides a new, multimessenger test of the weak equivalence principle (WEP), extending the WEP test with GWs and photons. Assuming that the arrival time delay between the GW signals from GW170817 and the photons from SGRB 170817A or the macronova is mainly attributed to the gravitational potential of the Milky Way, we demonstrate that the strict upper limits on the deviation from the WEP are Δγ< 1.4× 10− 3 for GW170817/macronova and Δγ< 5.9× 10− 8 for GW170817/SGRB 170817A. A much more severe constraint on the WEP accuracy can be achieved (∼ 0.9× 10− 10) for GW170817/SGRB 170817A when we consider the gravitational potential of the Virgo Cluster, rather than the Milky Way's gravity. This provides the tightest limit to date on the WEP through the relative differential variations of the γ parameter for two different species of particles. Compared with other multimessenger (photons and neutrinos) results, our limit is 7 orders of magnitude tighter than that placed by the neutrinos and photons from supernova 1987A, and is almost as good as or is an improvement of 6 orders of magnitude over the limits obtained by the low-significance neutrinos correlated with GRBs and a blazar flare.