Interferometer Signal Detection System for the VIRGO Experiment

VIRGO is a laser interferometer aiming at the first detection of gravitational waves emitted by astrophysical sources. The signal detection system consists of all the output optics and the electronics necessary for the measurement of the interferometer output signal. An output mode-cleaner has been developed in this context. The system has been installed at the detector site and is now being used for the central interferometer, the first step in the construction of VIRGO. The first results obtained so far are shown hereafter.