A MOBILE ATOM INTERFEROMETER FOR HIGH PRECISION MEASUREMENTS OF LOCAL GRAVITY

We present a new design for the mobile and robust gravimeter GAIN (Gravimetric Atom Interferometer), which is based on interfering ensembles of laser cooled ⁸⁷Rb atoms in an atomic fountain configuration. With a targeted accuracy of a few parts in 10¹⁰ for the measurement of local gravity, g, this instrument would offer about an order of magnitude improvement in performance over the best currently available absolute gravimeters. Together with the capability to perform measurements directly at sites of geophysical interest, this will open up the possibility for a number of interesting applications. We report on important subsystems of this atom interferometer, including a rack-mounted laser system and a compact vacuum chamber. Furthermore, a high flux 2-dimensional Magneto-optical trap capable of providing up to 10¹² atoms/second and a high-power laser system providing 6.4 W at 780 nm are presented.