Search for axion dark matter with the QUAX-LNF tunable haloscope

We report the first experimental results obtained with the new haloscope of the QUAX experiment located at Laboratori Nazionali di Frascati of INFN (LNF). The haloscope is composed of a OFHC Cu resonant cavity cooled down to about 30 mK and immersed in a magnetic field of 8 T. The cavity frequency was varied in a 6 MHz range between 8.831496 and 8.83803 GHz. This corresponds to a previously unprobed mass range between 36.52413 and 36.5511 mu eV. We don't observe any excess in the power spectrum and set limits on the axion-photon coupling in this mass range down to g a gamma gamma < 0.882 x 10 - 13 GeV-1 - 1 with the confidence level set to 90%.