ABSTRACT

The gravitational waves are space-time ripples caused by very violent phenomena, such as black holes’ collisions, supernovae’s explosions or the relic signal of the Big Bang that gave rise to the universe. In 2015, LIGO and the Virgo projects announced in parallel in Washington and in Cascina at the EGO site (European Gravitational Observatory) the first direct observation of a gravitational wave signal, announcing the birth of a new way to explore the Universe. At present, the realization of a third generation Gravitational Wave observatory (Einstein Telescope ET) is being pursued. After the Conceptual Design Study (CD) released by the original partners, a new phase is now open, with submission of the site proposal for a ET detector hosted in a large underground infrastructure. The feasibility study for the candidate site of Lula (Sardinia) was carried out through a CD’s scientific revision and a deep and strong interaction with the geomechanical needs.