The recent discovery of merging black holes suggests that a stochastic gravitational-wave background is within reach of the advanced detector network operating at design sensitivity. However, correlated magnetic noise from Schumann resonances threatens to contaminate observation of a stochastic background. In this paper, we report on the first effort to eliminate intercontinental correlated noise from Schumann resonances using Wiener filtering. Using magnetometers as proxies for gravitational-wave detectors, we demonstrate as much as a factor of two reduction in the coherence between magnetometers on different continents. While much work remains to be done, our results constitute a proof-of-principle and motivate follow-up studies with a dedicated array of magnetometers.
Bibliographical noteFunding Information:
MC is supported by the National Science Foundation Graduate Research Fellowship Program, under NSF grant number DGE 1144152. NC work is supported by NSF grant PHY-1505373. ET is supported through ARC FT150100281. We would like to acknowledge Luciano Papi for his assistance in the Villa Cristina measurements.
- Schumann resonances
- Wiener filter
- correlated noise