Sensitive Absolute Gravity Gradiometry Using Atom Interferometry
J. M. McGuirk, G. T. Foster, J. B. Fixler, M.J. Snadden, M. A. Kasevich
Abstract
We report the demonstration of a sensitive absolute gravity gradiometer based on light-pulse atom interference techniques. The gradiometer consists of two absolute accelerometers operated in a differential mode. We report a differential acceleration sensitivity of 4e-9 g/Hz^(1/2) and an inferred differential acceleration accuracy of less than 1e-9 g. This corresponds to a gravity gradient sensitivity of 4 E/Hz^(1/2) [1 E = 1e-9 s^(-2)] and an accuracy of better than 1 E for a 10 m separation between accelerometers. We demonstrate that the instrument can be used to detect nearby masses in a vibrationally noisy environment and characterize instrument sensitivity to spurious acceleration and rotation noise.