Subtraction of Newtonian Noise Using Optimized Sensor Arrays

TL;DR

This paper models Newtonian noise affecting gravitational wave detectors and demonstrates that optimized sensor arrays can subtract this noise effectively, significantly improving detector sensitivity.

Contribution

It introduces a new model for Newtonian noise and evaluates optimized sensor array schemes for effective noise subtraction in gravitational wave detectors.

Findings

Broadband noise mitigation factors close to 10 achieved

Significant sensitivity improvements in gravitational wave detection

Effective noise subtraction in both causal and acausal implementations

Abstract

Fluctuations in the local Newtonian gravitational field present a limit to high precision measurements, including searches for gravitational waves using laser interferometers. In this work, we present a model of this perturbing gravitational field and evaluate schemes to mitigate the effect by estimating and subtracting it from the interferometer data stream. Information about the Newtonian noise is obtained from simulated seismic data. The method is tested on causal as well as acausal implementations of noise subtraction. In both cases it is demonstrated that broadband mitigation factors close to 10 can be achieved removing Newtonian noise as a dominant noise contribution. The resulting improvement in the detector sensitivity will substantially enhance the detection rate of gravitational radiation from cosmological sources.