Detecting solar axions using Earth's magnetic field

Original · EN

We show that solar axion conversion to photons in the Earth's magnetosphere can produce an x-ray flux, with average energy 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 < 10⁻⁴ eV, a low-Earth-orbit x-ray detector with an effective area of 10⁴ cm², pointed at the solar core, can probe the photon-axion coupling down to 10⁻¹¹ GeV⁻¹, in one year. Thus, the sensitivity of this new approach will be an order of magnitude beyond current laboratory limits.