Correlated noise could impact the search for the gravitational wave background at future Earth-based gravitational-wave detectors. Due to the small distance ($\sim$ 400 m) between the different interferometers of the Einstein Telescope, correlated seismic noise could have a significant effect. To this extent, we study the seismic correlations at the Earth's surface, as well as underground, between seismometers and geophones separated by several hundreds of meters, in the frequency range 0.05 Hz - 50 Hz. Based on these correlated seismic fields we predict the levels of correlated Newtonian noise (NN). We construct upper limits on the allowed seismic coupling function such that correlated seismic noise does not affect the search for an isotropic gravitational wave background. Assuming a facility located 300 m below the surface, the impact on the search for a gravitational wave background of correlated NN from Rayleigh waves are found to be problematic up to $\sim$ 5 Hz. The NN from body waves, however, constitutes a serious threat to the search of a gravitational wave background. Correlated NN from body waves could be up to five to seven orders of magnitude above the planned sensitivity at $\sim$ 3 Hz and it could impede any search for a gravitational wave background below 40 Hz. With a factor 10 of NN reduction via NN cancellation in each interferometer, the effects of the NN on the stochastic search could be eliminated above 30 Hz.
Machine learning for gravitational-wave detection: surrogate Wiener filtering for the prediction and optimized cancellation of Newtonian noise at Virgo
The impact of seasonality over the sensitivity of Einstein Telescope and the SNR of CBC signals at the Sardinia candidate site
Scuola Normale Superiore（高等师范学院）；Istituto Nazionale di Fisica Nucleare（意大利国家核物理研究所）；Università di Milano Bicocca（米兰比可卡大学）；Istituto Nazionale di Geofisica e Vulcanologia（意大利国家地球物理与火山学研究所）；Universitá Federico II Napoli（那不勒斯费德里科二世大学）
Prospects for Observing Gravity-gradient Noise and Earthquake Gravity Signals with CHRONOS
National Institute of Physics, University of the Philippines - Diliman（菲律宾大学迪里曼分校国家物理研究所）；Center for High Energy and High Field (CHiP), National Central University（国立中央大学高能高场中心）；Institute of Physics, Academia Sinica（中央研究院物理研究所）；Institute of Particle and Nuclear Studies, High Energy Acceleration Research Organization (KEK)（高能加速器研究机构粒子与核研究部）
Science of Cryogenic sub-Hz cROss torsion bar detector with quantum NOn-demolition Speed meter (CHRONOS)
National Central University（中央大学）；Center for High Energy and High Field (CHiP), National Central University（国立中央大学高能高场中心）；Institute of Physics, Academia Sinica（中央研究院物理研究所）；Institute of Particle and Nuclear Studies, High Energy Acceleration Research Organization (KEK)（高能加速器研究机构粒子核研究部）；National Institute of Physics, University of the Philippines - Diliman（菲律宾大学迪利曼分校国家物理研究所）
