Flares as fingerprints of inner solar darkness

Understand

X-ray flares and other solar brightenings have been discarded as potential axion signatures.

• An axion X-ray signal must appear exclusively near the disk centre, and its spectrum must peak at ~4.2keV, contrary to observation.
• We argue here that due to Compton scattering off the (plasma) electrons the outward propagation of X-rays from axions converted near the Sun's surface can explain energy distribution and non direcivity.
• Simulation points at the photosphere as the birth place of the presumed axion conversion, implying an axion rest mass of ~0.01eV.