The site characterisation of future underground gravitational wave detectors is based on spectral properties of the low frequency seismic noise. The evaluation of the collected long term seismological data in the Mátra Gravitational and Geophysical Laboratory revealed some aspects that are not apparent in short term spectral noise characterisation. In this paper we survey the methodology. In particular, we argue that the spectral properties are best represented by percentiles of the data instead of the mode, because it is noisy, sensitive to the discretization and intrinsic averaging, therefore it is less suitable for a robust characterisation. The suitable cumulative measures are also scrutinized.

中文翻译：

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地下重力波探测器的地震噪声措施

未来的地下重力波探测器的位置特征是基于低频地震噪声的频谱特性。在Mátra重力和地球物理实验室对收集到的长期地震数据进行的评估揭示了一些在短期频谱噪声表征中不明显的方面。在本文中，我们概述了该方法。特别是，我们认为光谱特性最好用数据的百分位数而不是模式来表示，因为它有噪声，对离散化和本征平均敏感，因此不太适合进行稳健的表征。适当的累积量度也会被仔细检查。