Experimental Constraint on Axionlike Particles over Seven Orders of Magnitude in Mass

We use our recent electric dipole moment (EDM) measurement data to constrain the possibility that the HfF⁺ EDM oscillates in time due to interactions with candidate dark matter axionlike particles (ALPs). We employ a Bayesian analysis method which accounts for both the look-elsewhere effect and the uncertainties associated with stochastic density fluctuations in the ALP field. We find no evidence of an oscillating EDM over a range spanning from 27 nHz to 400 mHz, and we use this result to constrain the ALP-gluon coupling over the mass range 10⁻²²-10⁻¹⁵ eV. This is the first laboratory constraint on the ALP-gluon coupling in the 10⁻¹⁷-10⁻¹⁵ eV range, and the first laboratory constraint to properly account for the stochastic nature of the ALP field.