Introducing DMRadio-GUT, a search for GUT-scale QCD axions

Understand

The QCD axion is a leading dark matter candidate that emerges as part of the solution to the strong CP problem in the Standard Model.

• The coupling of the axion to photons is the most common experimental probe, but much parameter space remains unexplored.
• The coupling of the QCD axion to the Standard Model scales linearly with the axion mass; therefore, the highly-motivated region 0.4-120 neV, corresponding to a GUT-scale axion, is particularly difficult to reach.
• This paper presents the design requirements for a definitive search for GUT-scale axions and reviews the technological advances needed to enable this program.