Sar-Grav Laboratory and the third generation of gravitational waves detectors

Gravitational waves (GWs) detectors, measure tiny changes in the lengths of two connected arms several kilometers long, caused by a passing GW. The first and second generations of these interferometric detectors constrained the GW emission from several sources and have made the first direct detection of GWs. However, these detectors will not be sensitive enough for very precise astronomical studies of the GW sources, and new detector sites are required. The Einstein Telescope (ET) is a design concept for a European third-generation GW detector, which will be 10 times more sensitive than the current advanced instruments. The surroundings of Sos Enattos mine in Sardinia is being considered as a possible location for ET due to its very low seismic and anthropogenic noise. Such local characteristics allowed the construction of the Sar-Grav laboratory which aims to host underground experiments including low seismic noise experiments, cryogenic payloads, low frequency, and cryogenic sensor development. Nonetheless, a fundamental physics experiment, Archimedes, is the first experiment already under installation in the surface area.