Results of the search for dark matter-induced transient variation of fundamental constants with the GPS atomic clocks

Our GPS.DM collaboration has searched for dark-matter–induced transient variations in fundamental constants. We analyzed fourteen years of archival atomic-clock data from the satellites of the Global Positioning System (GPS). The targeted signature is the passage of a domain-wall–like boundary of a dark-matter "bubble," formed by self-interacting ultralight fields, sweeping across the GPS constellation. This search builds on our earlier work and now achieves the previously projected sensitivity. With a rate of false positives of one event per century, we identified several potential candidate dark matter events with signal-to-noise ratio above 6.80. However, a close examination of the speeds and directionality of these events are at odds with the prediction of the standard halo model. Moreover, the estimated coupling strengths are randomly positive or negative, which is inconsistent with the posited dark matter coupling. We found that a large fraction of candidate events correspond to several potential events occurring nearly simultaneously. Thereby, we dismissed these potential events and set an order of magnitude improved constraints on the transient variation of fundamental constants. We produced error bars for the estimated parameters of the remaining events.