Self-attraction effect and correction on three absolute gravimeters

TL;DR

This paper investigates the Self Attraction Effect in three absolute gravimeters, quantifies its impact through FEM simulations, and proposes corrections to improve measurement accuracy for international comparisons.

Contribution

It introduces a numerical FEM-based method to calculate and correct the Self Attraction Effect in absolute gravimeters, enhancing measurement precision.

Findings

SAE magnitude is around 1E-8 m/s2.

Corrections depend on instrument-specific height levels.

Method improves accuracy for international gravity comparisons.

Abstract

The perturbations of the gravitational field due to the mass distribution of an absolute gravimeter have been studied. The so called Self Attraction Effect (SAE) is crucial for the measurement accuracy, especially for the International Comparisons, and for the uncertainty budget evaluation. Three instruments have been analysed: MPG-2, FG5-238 and IMPG-02. The SAE has been calculated using a numerical method based on FEM simulation. The observed effect has been treated as an additional vertical gravity gradient. The correction (SAC) to be applied to the computed g value has been associated with the specific height level, where the measurement result is typically reported. The magnitude of the obtained corrections is of order 1E-8 m/s2.