The influence of transverse motion within an atomic gravimeter

TLDR

Transverse motion of the atomic cloud causes systematic effects such as Coriolis acceleration and wave‑front distortions. The study investigates limits on the long‑term stability and accuracy of a second‑generation cold‑atom gravimeter. The authors employ a protocol of four interleaved measurement configurations and opposite‑orientation runs to reject most systematic effects and separate Coriolis shifts from wave‑front distortions. Measurements at various atomic temperatures show that extrapolating to zero temperature—necessary to correct wave‑front distortion bias—is difficult.

Abstract

Limits on the long-term stability and accuracy of a second generation cold atom gravimeter are investigated. We demonstrate a measurement protocol based on four interleaved measurement configurations, which allows rejection of most of the systematic effects, but not those related to Coriolis acceleration and wave-front distortions. Both are related to the transverse motion of the atomic cloud. Carrying out measurements with opposite orientations with respect to the Earth's rotation vector direction allows us to separate the effects and correct for the Coriolis shift. Finally, measurements at different atomic temperatures are presented and analyzed. In particular, we show the difficulty of extrapolating these measurements to zero temperature, which is required in order to correct for the bias due to wave-front distortions.