Improved Dark Photon Sensitivity from a Superconducting-Radio-Frequency-Cavity Experiment
We report the refined dark-photon exclusion bound from Dark SRF’s pathfinder run. Our new result is driven by improved theoretical modeling of frequency instability in high-quality resonant experiments. Our analysis leads to a constraint that is an order of magnitude stronger than previously reported (corresponding to a signal-to-noise ratio that is 4 orders of magnitude larger). This result represents the world-leading constraint on non-dark-matter dark photons over a wide range of masses below 6 μeV and translates to the best laboratory-based limit on the photon mass 𝑚 𝛾 < 2.9 × 10 −48 g.
Kalia, Saarik [Univ. of Minnesota, Minneapolis, MN↗