The environmental monitoring system of VIRGO antenna for gravitational wave detection

The VIRGO antenna for gravitational wave detection is a very sensitive interferometer. All the noise sources are very low and continuously monitored by a complex monitoring system. This is a modular system whose architecture has been designed to guarantee the fulfillment of present and future VIRGO needs. Particular care has been devoted both to the management of probes different in type, sensitivity, and bandwidth distributed along the whole antenna and to the system integration within the main VIRGO data acquisition system architecture. The goal of this system is not only distributed synchronous acquisition, but also an on-line pre-analysis of environmental quantities necessary to implement a real-time data quality control.