QUPITER -- Space Quantum Sensors for Jovian-Bound Dark Matter

TL;DR

The paper addresses detecting ultralight dark matter (ULDM) bound to Jupiter by deploying space-based quantum sensors. It develops a magnetometer-based detector concept using SQUID readout to measure oscillating magnetic fields $\delta B = B_0 g \phi_0 \cos(\omega t)$ with $\phi_0 = \sqrt{2\rho_{\rm DM}}/m_\phi$ and $\omega = 2\pi f$, where the coupling $g = -g_e/m_e + g_\gamma$ arises from electron and photon interactions; the signal-to-noise ratio follows $\mathrm{SNR} = \mathcal{B} (g\sqrt{\rho_{\rm DM}}/m_\phi) (t/(\xi f))^{1/4}$. The work models a Jupiter-bound ULDM subhalo with density profile $\rho_\star$ governed by $R_\star$ and $R_{\rm ext}$, and coherence time $\tau_\star = 1/(m_\phi\beta^2) = m_\phi R_\star^2$, imposing $M_\star < {\rm Min}[ \tfrac{1}{2} M_{\rm Jup} (R_\star/R_{\rm Jup})^3, 0.01 M_{\rm Jup} ]$. Sensitivity projections for photon and electron couplings across masses $\sim 10^{-14}$–$10^{-8}$ eV suggest space-based detectors near Jupiter (and its moons Io, Callisto) can surpass terrestrial probes, potentially probing relaxion benchmarks at $\Lambda = 3$ TeV. By leveraging ongoing missions (JUNO, JUICE, Europa Clipper, Io Volcano Observer), this approach offers a practical path to test ULDM scenarios in the solar system with significant gains in sensitivity.

Abstract

We propose utilizing space quantum sensors to detect ultralight dark matter (ULDM) bound to planetary bodies, focusing on Jupiter as the heaviest planet in the solar system. Leveraging Jupiter's deep gravitational potential and the wealth of experience from numerous successful missions, we present strong sensitivity projections on the mass and couplings of scalar ULDM. Future space missions offer unique opportunities to probe the ULDM interactions using quantum sensors, including superconducting quantum interference device (SQUID) magnetometers. By measuring dark matter-induced magnetic field oscillations, we expect to achieve sensitivity orders of magnitude beyond the terrestrial probes and significantly improve detection prospects of theoretically motivated ULDM candidates.

Figures (2)

• Figure 1: Conceptual illustration of the proposed experimental setup. The yellow loops denote SQUID magnetometer pickup loops installed at two locations to detect magnetic-field oscillations (see the main text for detailed discussions). The blue cylindrical objects represent permanent magnets, which serve as sources of magnetic fields, depicted by red arrows. To suppress external magnetic noise, such as that from Jupiter’s magnetosphere, the entire apparatus can be enclosed within a (superconducting) shield.
• Figure 2: Sensitivity projections for the couplings of the scalar ULDM $\phi$ of mass $m_\phi$ to the photon, $d_\alpha$ (left panel), and to the electron, $d_{m_e}$ (right panel). The dotted and dashed purple lines represent theoretical predictions (see main text) Flacke:2016szyChoi:2016luuTsai:2021lly. The shaded gray region denotes constraints from equivalence principle experiments Wagner:2012uiBerge:2017ovyHees:2018fpg. The projections are shown for detectors placed on Earth, on the surface of Jupiter, and near the Jovian moons Io and Callisto.