Noise attenuators for gravitational wave experiments

The study of the weakest interaction in nature requires the highest degree of isolation of the experimental apparatus from the environment. We present an analytical and experimental study of the behaviour of a simple metallic structure (a cantilever beam) as an element of mechanical noise attenuators for gravity experiments. Extending previous analyses, we study the behaviour of cantilever springs in all the six degrees of freedom. We report the optimisation criteria and the attenuation obtainable with a multi-stage structure that uses cantilever springs as compliance elements. The agreement between theoretical predictions and the experimental results obtained with a test attenuator is very good.