Advanced VIRGO optical design

The 3km arm length Virgo detector located in Pisa, Italy, is the largest and most sensitive gravitational wave detector in Europe [1]. Around 2010 this instrument will undergo a major upgrade, called Advanced Virgo, aiming for a 10 times better sensitivity than initial Virgo detector [2].

[Virgo Detector]

Building Advanced Virgo includes the following upgrades [3]:

Other potentially beneficial upgrades currently under investigation are:

[AVOD graph]

The change from using only Power Recycling to more advanced optical topologies, such as the simultaneous use of Power and Signal Recycling or non-Gaussian beams, will increase the complexity of the system. Advanced VIRGO will thus face an increasingly difficult control problem and probably additional unwanted cross-coupling between ideally independent degrees of freedom. In addition, Advanced VIRGO will make use of higher circulating light power, which results in more stringent requirements for several interferometer parameters, including optical losses and the mirror positions. Therefore a detailed and thorough system design of Advanced Virgo will be required to reach a mature design.

Our group signs responsible for the optical design of Advanced Virgo, a key point within the project, connecting to all the other subsystems.

The next steps towards the Advanced Virgo optical design are: