Most of the mass of the Milky Way is contributed by its halo, presumably in the form of noninteracting cold dark matter. The axion is a compelling cold dark matter candidate. We report results from a search that probes the local Galactic halo axion density using the Sikivie radio frequency cavity technique. Candidates over the frequency range 550 MHz ≤ f ≤ 810 MHz (2.3 μeV ≤ m_a ≤ 3.4 μeV) were investigated. The absence of a signal suggests that the axions of Kim and Shifman, Vainshtein, & Zakharov contribute no more than 0.45 GeV cm~(-3) of mass density to the local dark matter halo over this mass range.
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