Regular Article

A network of superconducting gravimeters as a detector of matter with feeble nongravitational coupling^⋆

¹ School of Physics, Peking University, Beijing, P.R. China
² The Oskar Klein Centre for Cosmoparticle Physics, Department of Physics, Stockholm University, AlbaNova, Stockholm 10691, Sweden
³ Nordita, KTH Royal Institute of Technology and Stockholm University, Roslagstullbacken 23, Stockholm 10691, Sweden
⁴ Helmholtz Institut, Johannes Gutenberg-Universität Mainz, Mainz 55128, Germany
⁵ Department of Physics, University of California, Berkeley, CA 94720, USA
⁶ Department of Physics, California State University – East Bay, Hayward, CA, USA
⁷ Department of Physics and Astronomy, University of California, Riverside, CA, USA
⁸ GFZ German Research Centre for Geosciences, Telegrafenberg, Potsdam, Germany

^a e-mail: figueroa@uni-mainz.de

Received: 5 February 2020
Received in final form: 31 March 2020
Published online: 11 June 2020

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 μHz. 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 10¹⁴ 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.