Speaker
Description
Increasing sensitivity of GW detectors in the low-frequency band is important for studying the intermediate mass black holes and accumulating signal from the lighter binary systems. Existing gravitational-wave detectors are limited at low frequencies by seismic noise and mode cross-coupling. Seismic isolation at low frequencies is challenging due to a tilt injection, reduced seismometer response and technical noises.
We suggest an inertial seismic isolation system based on interferometric sensing of the reference mass position in all degrees of freedom. Reference mass is suspended from the platform, which is actuated so that position of the platform is constant relative to the reference mass. This closed loop operation impose the reference mass stability to the platform. The platform may be used as an initial seismic isolated platform for suspension of the GW detector’s test masses.
Suggested design has advantages of keeping all DoF simultaneously quiet; very low tilting resonance minimise tilt-coupling; low-noise sensors and high-quality fused silica suspension minimise sensing and thermal noise.
