From SuperMAG to SNIPE Hunt: Using the Earth to search for ultralight dark matter
by
IFAE Seminar Room
In-person
Ultralight particles, such as dark photons or axions, are exciting candidates for dark matter that require novel detection schemes to probe. If these candidates couple to electromagnetism, they can generate observable electromagnetic fields inside an experimental apparatus, which scale with the apparatus's size. In this talk, I will summarize recent efforts to utilize the Earth as an apparatus for the detection of extremely low-mass dark matter. Dark-photon or axion dark matter can source an oscillating magnetic field signal at the Earth's surface, which can be detected with a global array of unshielded magnetometers. This field is spatially coherent across the entire Earth's surface, and its magnitude is enhanced by the large radius of the Earth. I will discuss experimental searches for this effect in existing datasets maintained by the SuperMAG collaboration and dedicated observations by the SNIPE Hunt collaboration. These initiatives represent the strongest experimental constraints on dark-photon and axion parameter space across a wide mass range. I will also discuss a proposed technique to probe higher masses by measuring the local curl of the magnetic field.
Dorian Amaral, Elia Bertoldo, Clarisse Prat, Francesco Sciotti