Axion haloscope experiment using 18T HTS magnet and JPC

Abstract

Dark matter and dark energy make up more than 95% of the universe. Among these components, dark matter has only gravitational interactions. Axion is one of the strongest candidates of the dark matter. If axion exists, it may be the solution to the strong CP problem. In order to detect the dark matter axion, we design an axion haloscope experiment. The experiment is equipped with 18 T High Temperature Superconducting (HTS), high quality factor microwave cavity with copper tuning-rod, and a Josephson Parametric Convertor (JPC), the quantum-noise-limited amplifier, and dilution refrigerator. The detector assembly has done and the first axion data was taken with this halosope detector. The scan frequency range is 4.7789 GHz to 4.8094 GHz (30.5 MHz range). There is no significant signal which is consistent with the dark matter axion on observed frequency range. The upper bounds of axion photon coupling constant $g_{a \gamma \gamma}$ are set $0.98 \times |g_{a \gamma \gamma}^{\text{KSVZ}}|$ in the mass ranges of 19.764 to 19.771 $\mu$eV, $1.76 \times |g_{a \gamma \gamma}^{\text{KSVZ}}|$ in the mass ranges of 19.772 to 19.863 $\mu$eV, and $1.11 \times |g_{a \gamma \gamma}^{\text{KSVZ}}|$ in the mass ranges of 19.863 to 19.890 $\mu$eV with 90% confidence level, respectively.