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arXiv · gr-qc/9911044

Inertial Control of the VIRGO Superattenuator

Giovanni Losurdo
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Abstract

The VIRGO superattenuator (SA) is effective in depressing the seismic noise below the thermal noise level above 4 Hz. On the other hand, the residual mirror motion associated to the SA normal modes can saturate the dynamics of the interferometer locking system. This motion is reduced implementing a wideband (DC-5 Hz) multidimensional control (the so called inertial damping) which makes use of both accelerometers and position sensors and of a DSP system. Feedback forces are exerted by coil-magnet actuators on the top of the inverted pendulum. The inertial damping is successful in reducing the mirror motion within the requirements. The results are presented.

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Giovanni Losurdo. 1999-11-11. Inertial Control of the VIRGO Superattenuator. https://doi.org/10.1063/1.1291876

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