title: Detecting solar axions using Earth's magnetic field.
abstract: We show that solar axion conversion to photons in the Earth's magnetosphere can produce an x-ray flux, with average energy omega approximately 4 keV, which is measurable on the dark side of the Earth. The smallness of the Earth's magnetic field is compensated by a large magnetized volume. For axion masses m(a) less, similar10(-4) eV, a low-Earth-orbit x-ray detector with an effective area of 10(4) cm(2), pointed at the solar core, can probe the photon-axion coupling down to 10(-11) GeV-1, in 1 yr. Thus, the sensitivity of this new approach will be an order of magnitude beyond current laboratory limits.
authors.affiliation: Department of Physics, University of Wisconsin, Madison, Wisconsin 53706, USA.
authors.forename: Hooman
authors.initials: H
authors.lastname: Davoudiasl
authors.forename: Patrick
authors.initials: P
authors.lastname: Huber