Observation of a potential future sensitivity limitation from ground motion at LIGO Hanford
Observation of a potential future sensitivity limitation from ground motion at LIGO Hanford
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DOI：
10.1103/physrevd.101.102002
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发表时间：
2020-05-05
影响因子：
5
通讯作者：
Venkateswara, K.
中科院分区：
文献类型：
--
作者：
Harms, J.;Bonilla, E. L.;Venkateswara, K.
在引力波探测器中首次探测到地球引力噪声是一项艰巨的挑战。在环境传感器的帮助下，通过估计环境传感器和检测器之间的相关性，原则上可以在噪声变得占主导地位之前实现。主要的复杂性是解开环境和探测器之间的不同耦合机制。在本文中，我们分析了在2016年和2017年第二次科学运行期间记录的地面运动和LIGO应变数据h（t）之间的物理耦合和相关性之间的关系。我们发现，与地面运动相关的所有噪声都比主要的低频仪器噪声低一个数量级以上，并且在地面和h（t）之间的部分频谱上的主要耦合是通过隔震系统的残余耦合。我们还提出了最准确的重力耦合模型，到目前为止，从地震台阵的数据的详细分析的基础上。尽管我们尽了最大的努力，但我们无法明确地识别数据中的引力耦合，但我们改进的模型证实了先前的预测，即引力耦合可能已经在低频引力波观测波段的部分区域中主导了线性地-h（t）耦合。
A first detection of terrestrial gravity noise in gravitational-wave detectors is a formidable challenge. With the help of environmental sensors, it can in principle be achieved before the noise becomes dominant by estimating correlations between environmental sensors and the detector. The main complication is to disentangle different coupling mechanisms between the environment and the detector. In this paper, we analyze the relations between physical couplings and correlations that involve ground motion and LIGO strain data h(t) recorded during its second science run in 2016 and 2017. We find that all noise correlated with ground motion was more than an order of magnitude lower than dominant low-frequency instrument noise, and the dominant coupling over part of the spectrum between ground and h(t) was residual coupling through the seismic-isolation system. We also present the most accurate gravitational coupling model so far based on a detailed analysis of data from a seismic array. Despite our best efforts, we were not able to unambiguously identify gravitational coupling in the data, but our improved models confirm previous predictions that gravitational coupling might already dominate linear ground-to-h(t) coupling over parts of the low-frequency, gravitational-wave observation band.