Results from a High-Sensitivity Search for Cosmic Axions
  We report the first results of a high-sensitivity (10^{-23} Watt) search for light halo axions through their conversion to microwave photons. At 90 percent confidence we exclude a KSVZ axion of mass 2.9 x 10^{-6} eV to 3.3 x 10^{-6} eV as the dark matter in the halo of our Galaxy. 
C. Hagmann, D. Kinion, W. Stoeffl, K. van Bibber, E. Daw, H. Peng,   Leslie J Rosenberg, J. LaVeigne, P. Sikivie, N. Sulliva...