Search for variability in Newtons constant using local gravitational acceleration measurements

We analyze the IGETS based gravitational acceleration measurements to search for a variability in Newtons constant $G$, as a complement to the analysis carried out in arXiv:2103.11157. To understand the variation in gravitational acceleration, we fit the aforementioned data to a constant model, two sinusoidal models, and a linear model. We find that none of the four models provide a good fit to the data, showing that there is no evidence for periodicity or linear temporal variation in the acceleration measurements. Based on the sinusoidal models, we infer that the relative variance of $G$ is $leqslant 2 times 10^{-9}$, which is about four orders of magnitude more stringent than the amplitude of periodic variations inferred from previous $G$ measurements. From the linear model, we obtain $frac{dot{G}}{G} < 2.14 times 10^{-10} rm{yr^{-1}}$.