Results of a Search for Cold Flows of Dark Matter Axions.pdf

Results of a Search for Cold Flows of Dark Matter Axions L. Duffy, P. Sikivie, and D.B. Tanner Physics Department, University of Florida, Gainesville, FL 32611 S. Asztalos, C. Hagmann, D. Kinion, L. J Rosenberg, K. van Bibber, and D. Yu Lawrence Livermore National Laboratory, Livermore, CA 94550 R.F. Bradley National Radio Astronomy Observatory, Charlottesville, VA 22903 (May 5, 2005) Theoretical arguments predict that the distribution of cold dark matter in spiral galaxies has 5 peaks in velocity space associated with non-thermalized flows of dark matter particles. We searched 0 for the corresponding peaks in the spectrum of microwave photons from axion to photon conversion 0 in the cavity detector of dark matter axions. We found none and place limits on the density of any 2 local flow of axions as a function of the flow velocity dispersion over the axion mass range 1.98 to y 2.17 µeV. a M PACS numbers: 14.80.Mz, 95.35.+d, 98.35.Gi 1 1 I. Introduction may be the outcome of an early epoch of “violent relax- ation” [9] of the galactic halo. However, there are excel- 1 The axion [1,2] is a light pseudo-scalar particle whose lent reasons to believe that a large fraction of the local v existence would explai