Self-attraction mapping and an update on local gravitational acceleration measurement in BIPM Kibble balance

Abstract

The self-attraction effect needs to be evaluated and corrected towards a 10−9 level absolute determination of the local gravitational acceleration g in Kibble balance experiments. In this paper, the self-attraction effect of the BIPM Kibble balance apparatus is modelled by linking the gravitational field to the electrical field based on an electrostatic finite element analysis. A mapping of the gravitational field with different construction segments of the apparatus is presented, yielding a total correction of Gal at the mean trajectory position. Experimental measurements are carried out to check the self-attraction model. Based on the obtained result and previous measurements, we updated the g determination along the measurement trajectory for the forthcoming Planck constant measurement.