Recent progress on the Axion Dark Matter eXperiment (ADMX)

The Axion Dark Matter eXperiment (ADMX) is one of the three “Generation-2” direct dark matter searches and the only one dedicated to finding the axion. It looks for axions that convert into photons through the Primakoff process in the presence of a strong magnetic field. The mass of the axion is unknown but expected to be ~few to tens of $\mu$eV, which corresponds to photons in the GHz range. The expected signal power is of the order $10^{-24}$ W, which puts stringent requirements on the system’s noise level. ADMX has recently started its Generation-2 data run with the recent upgrades of a dilution refrigerator, which cools the system to sub-K temperature suppressing the thermal background noise and tunable, near quantum noise-limited SQUID amplifiers. This talk will summarize the current status and operation of ADMX experiment as it searches for dark matter axions.