Speaker
Description
Astrophysical observations give overwhelming evidence for the existence of dark matter, and yet we know little about what they might be. Axion is a compelling candidate, as it also provides a solution to the strong CP problem in quantum chromodynamics (QCD) as proposed by Peccei & Quinn. I will present the results from the Haloscope at Yale Sensitive to Axion CDM (HAYSTAC) experiment, which scanned for axions between 17.28 – 18.44 μeV and 18.71–19.46 μeV. No statistically significant evidence of an axion signal was observed, excluding couplings of |gγ|≥2.75×|gγKSVZ| and |gγ|≥2.96×|gγKSVZ| at the 90% confidence level over the respective regions. By combining this data with previously published results using HAYSTAC's squeezed state receiver, we have scanned a total of 2.27 μeV of parameter space between 16.96 – 19.46 μeV, excluding | gγ |≥2.86×| gγKSVZ | at the 90% confidence level. These results demonstrate the squeezed state receiver's ability to probe axion models over a significant mass range while achieving a scan rate enhancement relative to a quantum-limited experiment.
