Search for Dark Matter with a global network of (co)magnetometers (GNOME)

Self-compensated comagnetometers are promising sensors for exotic beyond-the-standard-model fields and high-precision metrology. We propose and demonstrate a general method to calibrate the response of an atomic comagnetometer to any possible perturbation of the atomic spins. This is especially relevant in the context of the Global Network of Optical Magnetometers (GNOME), where we look for transient and background signals from the dark matter. I will discuss how to model and search for such events, including encounters with axion domain walls and Q-balls.