Axion dark matter experiment: Run 1B analysis details

Abstract

Searching for axion dark matter, the ADMX Collaboration acquired data from January to October 2018, over the mass range $2.81--3.31\text{ }\text{ }\mathrm{\ensuremath{\mu}}\mathrm{eV}$, corresponding to the frequency range 680--790 MHz. Using an axion haloscope consisting of a microwave cavity in a strong magnetic field, the ADMX experiment excluded Dine-Fischler-Srednicki-Zhitnisky (DFSZ) axions at 90% confidence level and 100% dark matter density over this entire frequency range, except for a few gaps due to mode crossings. This paper explains the full ADMX analysis for run 1B, motivating analysis choices informed by details specific to this run.