A network of precision gravimeters as a detector of matter with feeble nongravitational coupling

TL;DR

This paper investigates the potential of a global gravimeter network to detect hidden matter with weak nongravitational interactions trapped inside Earth, setting constraints on such matter's properties.

Contribution

It introduces a novel method using existing gravimeter data to search for feebly interacting matter within Earth, providing new limits on its mass and oscillation amplitude.

Findings

No evidence found for matter with mass > 10^14 kg oscillating at 300 μHz.

Constraints established on the existence of such matter within Earth's interior.

Potential for improved sensitivity with better noise understanding and data analysis.

Abstract

Hidden matter that interacts only gravitationally would oscillate at characteristic frequencies when trapped inside of Earth. For small oscillations near the center of the Earth, these frequencies are around 300 $\mu$Hz. Additionally, signatures at higher harmonics would appear because of the non-uniformity of Earth's density. In this work, we use data from a global network of gravimeters of the International Geodynamics and Earth Tide Service (IGETS) to look for these hypothetical trapped objects. We find no evidence for such objects with masses on the order of 10$^{14}$ kg or greater with an oscillation amplitude of 0.1 $r_e$. It may be possible to improve the sensitivity of the search by several orders of magnitude via better understanding of the terrestrial noise sources and more advanced data analysis.