G-Pisa gyrolaser

G-Pisa is an experiment which is investigating the possibility to operate a laser-gyro with area less than 1 m² and high sensitivity in order to improve the performances of the mirrors suspension of the gravitational wave antenna Virgo. The experimental set-up consists of a 4 mirrors square cavity, the mechanical drawing allows us to scale the area from 2 down to 0.81 m². G-Pisa is working since July 2008, in the following the results so far obtained are reported. At low frequency, below 1 Hz, the sensitivity is typically in the range of 10^-8 rad/s/radicHz, it has been checked that G-Pisa is working properly in single mode and multimode good stable operation has been observed up to 4 mode.