Speaker
Description
Recently [Phys. Rev. D 112 (2025) 035003; arXiv:2506.18595 [hep-ph]], we proposed an experimental project called the Cosmological Axion Sarov Haloscope (CASH), aimed at searching for dark-matter axions via their conversion into microwave photons in a magnetic field. The key feature of the experiment is the use of Josephson-junction single-photon detectors (JJ SPDs) operating at ultralow temperatures, where thermal noise is negligibly small. This allows us to probe the axion–photon coupling with ultrahigh precision, with sensitivity to gaγγ∼(10^{−14}–10^{−15}) GeV^{−1} for axion masses in the range 38–54 μeV, motivated by generic QCD axion models.
In this talk, we also describe the current preparation for the launch of the first stage of the experiment: measurements of the parameters of fabricated JJ SPDs and a high-quality-factor cavity. In addition, we discuss the design features of tunable cavities and existing prototypes.
