
Session H20 - Gravitational Radiation - Experiment.
MIXED session, Sunday morning, April 30
102A, LBCC
We have developed an advanced and simplified filter for attenuation of vertical seismic noise. This new design is based on the non-linear behavior of curved and mechanically constrained blades instead of the geometric anti-spring effect of the original design. Some of the internal filter resonances are eliminated or increased in frequency. The main internal blade mode frequency, however, is lowered by 30The wireless concept permits more compact assemblies, with the penalty of a smaller payload rating of a few hundred Kgs (instead of almost a ton). This makes the new units suitable for lower level filters in a SAS chain and for their implementation in multiple seismic attenuation chains in a vacuum chamber. These wireless filters will also be beneficial for use in smaller interferometers like TAMA.