F. Frasconi

The construction status of the VIRGO interferometric antenna is presented. The detection of  Gravitational Waves (GW), with this kind of apparatus, is limited at low frequencies by seismic noise. For this reason a sophisticated isolation system, called Super-Attenuator (SA), has been conceived. It consists of a cascade of metallic masses, drum shaped, which are connected each other by means of a metallic wire. This chain of second order mechanical low pass filters will reduce the transmission of the seismic noise on the optical components.

The VIRGO antenna, presently in the installation phase at Cascina not far away from Pisa (Italy), has been designed to have a bandwidth starting from a few hertz up to 10 kHz. An overview of the entire apparatus as well as a description of the suspension system and its performances will be reported.