Search for ultralight dark matter in the SuperMAG high-fidelity dataset

TL;DR

This study utilizes the high-fidelity SuperMAG magnetometer dataset with 1-second resolution to search for ultralight dark matter signals, filling the gap between previous low- and high-frequency searches, and sets new constraints on dark matter parameters.

Contribution

It introduces the use of high-resolution SuperMAG data for ultralight dark matter searches, providing the first constraints in this intermediate frequency range.

Findings

No robust dark matter candidates detected.

Set leading constraints on ultralight dark matter in the 10^{-3} to 1 Hz range.

Surpassed astrophysical constraints around 2×10^{-15} eV.

Abstract

Ultralight dark matter, such as kinetically mixed dark-photon dark matter (DPDM) or axionlike-particle dark matter (axion DM), can source an oscillating magnetic-field signal at Earth's surface. Previous work searched for this signal in a publicly available dataset of global magnetometer measurements maintained by the SuperMAG collaboration. This ``low-fidelity" dataset reported measurements with a 1-minute time resolution, allowing the search to set leading direct constraints on DPDM and axion DM with Compton frequencies $f_\mathrm{DM}\leq1/(1\,\mathrm{min})$ [corresponding to masses $m_\mathrm{DM}\leq7\times10^{-17}\,\mathrm{eV}$]. More recently, a dedicated experiment undertaken by the SNIPE Hunt collaboration has also searched for this same signal at higher frequencies $f_\mathrm{DM}\geq0.5\,\mathrm{Hz}$ (or $m_\mathrm{DM}\geq2\times10^{-15}\,\mathrm{eV}$). In this work, we search for this signal of ultralight DM in the SuperMAG ``high-fidelity" dataset, which features a 1-second time resolution, allowing us to probe the gap in parameter space between the low-fidelity dataset and the SNIPE Hunt experiment. The high-fidelity dataset exhibits lower geomagnetic noise than the low-fidelity dataset and features more data than the SNIPE Hunt experiment, making it a powerful probe of ultralight DM. Our search finds no robust DPDM or axion DM candidates. We set constraints on DPDM and axion DM parameter space for $10^{-3}\,\mathrm{Hz}\leq f_\mathrm{DM}\leq0.98\,\mathrm{Hz}$ (or $4\times10^{-18}\,\mathrm{eV}\leq m_\mathrm{DM}\leq4\times10^{-15}\,\mathrm{eV}$). Our results are the leading direct constraints on both DPDM and axion DM in this mass range, and our DPDM constraint surpasses the leading astrophysical constraint in a narrow range around $m_{A'}\approx2\times10^{-15}\,\mathrm{eV}$.