A vertical inertial sensor with interferometric readout
arXiv:2208.09320 · doi:10.1088/1361-6382/aca45b
Abstract
High precision interferometers such as gravitational-wave detectors require complex seismic isolation systems in order to decouple the experiment from unwanted ground motion. Improved inertial sensors for active isolation potentially enhance the sensitivity of existing and future gravitational-wave detectors, especially below 30 Hz, and thereby increase the range of detectable astrophysical signals. This paper presents a vertical inertial sensor which senses the relative motion between an inertial test mass suspended by a blade spring and a seismically isolated platform. An interferometric readout was used which introduces low sensing noise, and preserves a large dynamic range due to fringe-counting. The expected sensitivity is comparable to other state-of-the-art interferometric inertial sensors and reaches values of at 100 mHz and at 1 Hz. The potential sensitivity improvement compared to commercial L-4C geophones is shown to be about two orders of magnitude at 10 mHz and 100 mHz and one order of magnitude at 1 Hz. The noise performance is expected to be limited by thermal noise of the inertial test mass suspension below 10 Hz. Further performance limitations of the sensor, such as tilt-to-vertical coupling from a non-perfect levelling of the test mass and nonlinearities in the interferometric readout, are also quantified and discussed.
References in corpus (16)
- Science Case for the Einstein Telescope
- The Sensitivity of the Advanced LIGO Detectors at the Beginning of Gravitational Wave Astronomy
- Sensitivity and Performance of the Advanced LIGO Detectors in the Third Observing Run
- Seismic isolation of Advanced LIGO: Review of strategy, instrumentation and performance
- A Horizon Study for Cosmic Explorer: Science, Observatories, and Community
- A high-precision mechanical absolute-rotation sensor
- Monolithic Geometric Anti-Spring Blade
- Gas damping force noise on a macroscopic test body in an infinite gas reservoir
- A compact, large-range interferometer for precision measurement and inertial sensing
- Passive, free-space laser gyroscope
- A 6D interferometric inertial isolation system
- Automatic cross-talk removal from multi-channel data
- Passive optical gyroscope with double homodyne readout
- Huddle test measurement of a near Johnson noise limited geophone
- A six degree-of-freedom fused silica seismometer: Design and tests of a metal prototype
- Modeling and Experiment of the Suspended Seismometer Concept for Attenuating the Contribution of Tilt Motion in Horizontal Measurements