First Results from ABRACADABRA-10 cm: A Search for Sub- μeV Axion Dark Matter

Abstract

The axion is a promising dark matter candidate, which was originally proposed to solve the strong-CP problem in particle physics. To date, the available parameter space for axion and axionlike particle dark matter is relatively unexplored, particularly at masses ma1 μeV. ABRACADABRA is a new experimental program to search for axion dark matter over a broad range of masses, 10-12ma10-6 eV. ABRACADABRA-10 cm is a small-scale prototype for a future detector that could be sensitive to the QCD axion. In this Letter, we present the first results from a 1 month search for axions with ABRACADABRA-10 cm. We find no evidence for axionlike cosmic dark matter and set 95% C.L. upper limits on the axion-photon coupling between gaγγ<1.4×10-10 and gaγγ<3.3×10-9 GeV-1 over the mass range 3.1×10-10-8.3×10-9 eV. These results are competitive with the most stringent astrophysical constraints in this mass range.