Search for stochastic fluctuations of ultralight bosonic dark matter fields with a global magnetometer network

If dark matter is an ultralight bosonic field that conforms to the standard halo model, then the bosons are virialized in the gravitational potential of the Milky Way. Due to the bosons' randomized velocities, different field modes interfere with one another resulting in stochastic fluctuations of the net field [Centers et al., arXiv:1905.13650 (2020)]. If the coherence length of the virialized bosonic field is large compared to the diameter of the Earth, global sensor networks could detect common mode fluctuations of the bosonic dark matter field. Here we present preliminary results of a search for correlated fluctuations in data from the Global Network of Optical Magnetometers for Exotic physics [GNOME, see Afach et al., Physics of the Dark Universe 22, 162 (2018)].