The VIRGO superattenuator (SA) is effective in suppressing seismic noise below the expected thermal noise level above 4 Hz. However, the residual mirror motion associated with the SA normal modes can saturate the interferometer control system. This motion is reduced by implementing a wideband (DC-5 Hz) multidimensional active control (the so-called inertial damping) which makes use of both accelerometers and position sensors and of a digital signal processing (DSP) system. Feedback forces are exerted by coil-magnet actuators on the top of an inverted pendulum pre-isolator stage. The residual root mean square motion of the mirror in 10 s is less than 0.1 mum.
Losurdo, G., The VIRGO, C., Cuoco, E. (2002). The inertial damping of the VIRGO superattenuator and the residual motion of the mirror. CLASSICAL AND QUANTUM GRAVITY, 19(7), 1631-1637.
The inertial damping of the VIRGO superattenuator and the residual motion of the mirror
Cuoco E.
2002
Abstract
The VIRGO superattenuator (SA) is effective in suppressing seismic noise below the expected thermal noise level above 4 Hz. However, the residual mirror motion associated with the SA normal modes can saturate the interferometer control system. This motion is reduced by implementing a wideband (DC-5 Hz) multidimensional active control (the so-called inertial damping) which makes use of both accelerometers and position sensors and of a digital signal processing (DSP) system. Feedback forces are exerted by coil-magnet actuators on the top of an inverted pendulum pre-isolator stage. The residual root mean square motion of the mirror in 10 s is less than 0.1 mum.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
