COLLOQUIUM "Drilling the South of the Netherlands to detect Gravitational Waves" by Wim Walk (Nikhef)

Friday 8 Mar 2024, 11:00 → 12:00 Europe/Amsterdam

The Euroregion Meuse-Rhine (EMR) is a candidate site for constructing the Einstein Telescope (ET). We expect a decision on where ET will be built sometime end 2026. To enable such a decision, a comprehensive technical program has been developed to characterise the EMR site and determine whether a subsurface trajectory is cost-effectively realisable to specifications. Investigations are required to demonstrate that the subsurface is of sufficient quality to construct at least one trajectory, including the excavation of tunnels, caverns and access shafts, within a specified budget. Furthermore, we need to establish that the selected trajectory is socially, politically and environmentally acceptable. Finally we need to show that the proposed trajectory can be expected to have an acceptable noise budget (gravitational disturbance) at the corner points for the instruments to perform to sensitivity requirements. In this presentation a selection of the current plans and activities to characterize the site are  discussed. Sub-surface measurements to establish rock quality and noise levels are described, including drilling boreholes, seismic, electrical resistivity and gravity measurements. In particular the drilling campaign that started this week is described and its purpose explained. At the end of the presentation a live video connection is made with the current drill site at Hombourg, Belgium.