The First data of axion mass range around 2.5 GHz at CAPP in Korea*

The flagship axion experiment of CAPP (Center for Axion and Precision Physics Research) of IBS in Korea, CULTASK (CAPP's Ultra Low Temperature Axion Search in Korea) has been built on a low vibration facility at Munji campus of KAIST (Korea Advanced Institute for Science and Technology). We have prepared one complete direct-search axion experiment with a powerful dilution refrigerator and a 8T superconducting magnet, ready to explore an axion mass range of 2\textasciitilde 2.5 GHz. A resonant cavity (10 cm OD) with a sapphire tuning rod driven by a piezoelectric actuator system was successfully cooled down below 40 mK and showed a very high unloaded Q-factor (\textasciitilde 130,000) even under 8T magnetic field. The RF receiver employs a 1K HEMT amplifier out of the cavity, but the design is flexible enough to replace it with SQUID amplifier when R{\&}D is completed soon. I will present the results of physics data runs in this mass range and our future plans.