Virgo has been updated: the new Advanced Virgo was born
The 20 February 2017 was a day of celebration at the EGO (European Gravitational Observatory): in the countryside of Cascina (Pisa) the new Virgo 2.0 was inaugurated. The Italian-French gravitational interferometer, already present since 2003, has been “updated and enhanced” (hence the name Advanced Virgo) after 5 years of work and about 24 million euros of investment.
Soon the new gravitational wave detector will join the two Americans of LIGO (Laser Interferometer Gravitational-Wave Observatory), the famous couple that allowed last September to capture the first ever signal of a gravitational wave (Virgo was off because of the “restructuring”).
«Now we are completing the last steps to have a network of interferometers that will be able to tell us not only that a spectacular catastrophe has happened somewhere in the Universe, but even where it happened with good accuracy», says Fernando Ferroni, president of INFN.
A bit like earthquakes on Earth, Advanced Virgo will compose the missing piece to perform a sort of “spatial triangulation“, which will provide the telescopes with the coordinates of a sufficiently circumscribed portion of the universe, in which to look for electromagnetic counterparts of the event that produced gravitational waves.
«From 2011 to 2017 the physics of gravity has undergone an amazing acceleration: the birth of the global collaboration LIGO-Virgo, the construction of second-generation interferometers, the first detection of gravitational waves, and now the end of the construction of Advanced Virgo», underlines Federico Ferrini, director of EGO.
«Soon – continues – we’ll be in operation, together with colleagues from LIGO who await with our own trepidation the completion of the tuning of our interferometer, because three machines are essential to be able to proceed with truly significant scientific programs, and explore still unknown horizons».
Advanced Virgo has undergone a sensitivity increase equal to a factor of 10 compared to Virgo and, consequently, will allow the exploration of a volume of cosmos 1000 times greater than that previously obtained.
Here are the most important changes made on the new detector:
- New optical apparatus with heavier and performing mirrors
- The most powerful latest generation electronics
- Sophisticated system of aberrations compensations
- Enhanced seismic isolation system
- Diffuse light damping systems
- Improvement of the vacuum system in the arms
In addition to the two LIGOs in the United States and Virgo in Italy, the KAGRA interferometer in Japan is under construction, which will become operational in 2019.