Seismic Noise Effect on Equivalence Principle TestUsing Free-Fall Interferometry

A simple interferometer was used to monitor the seismic noise effect on the equivalence principle test using the free-fall interferometric method. The experimental result showed that this effect was below λ/100, where λ is the wavelength of the laser beam, and the uncertainty of the differential gravity acceleration of the individual free-fall result due to this effect was about 0.6μGal.