Correlated Detection of sub-mHz Gravitational Waves by Two Optical-Fiber Interferometers

Abstract

Results from two optical-fiber gravitational-wave interferometric detectors are reported. The detector design is very small, cheap and simple to build and operate. Using two detectors has permitted various tests of the design principles as well as demonstrating the first simultaneous detection of correlated gravitational waves from detectors spatially separated by 1.1km. The frequency spectrum of the detected gravitational waves is sub-mHz with a strain spectral index a=-1.4 +/- 0.1. As well as characterising the wave effects the detectors also show, from data collected over some 80 days in the latter part of 2007, the dominant earth rotation effect and the earth orbit effect. The detectors operate by exploiting light speed anisotropy in optical-fibers. The data confirms previous observations of light speed anisotropy, earth rotation and orbit effects, and gravitational waves.