Speaker
Description
Seismic noise is characterized by different features and sources, and it affects the detectors in different ways [Daw2004, Beker2011, Accadia2012, MacLeod2012, Trozzo2022, Figura2022]. Most of the contributions come at the microseismic peak (0.1-0.5 Hz) due to the Ocean waves exciting surface waves on the ground. At lower frequencies, the variation of gravity gradients due to mass motion on or below the ground induce a change in the density of the ground around the masses, affecting their stability (Newtonian Noise). The ground motion along the rotational degrees of freedom (DOF), often referred to as "tilt", is the contribution explored in my talk. Tilt affects not only the components of the detectors (up to, ultimately, the test masses) but also the sensors dedicated to detecting motions in other DOFs because it couples with other DOFs, providing the sensors with spurious output in their measurements and approximation in the control systems, due to the limitations in targeting and controlling this motion. I will review the state of the art (review paper now under submission) and introduce the Rotation Sensor developed at UWA, plans for testing and adding it to the seismic array at the Gingin High Optical Power Facility for 6 DoF seismology.