Solar flares are sudden explosive processes that convert the energy of the magnetic field into the kinetic energy of electrons and ions. Since the beginning of the century, millimeter observations of solar flares became routinely possible at a few frequencies with limited spatial resolution (see Kaufmann 2012, as a review). One of the most puzzling aspects of the observations at millimeter wavelengths (200-400 GHz) is the presence, in some flares, of a bright spectral component that grows with frequency. This emission is about a hundred trillion times more powerful than the power from the active millimeter full body scanners used in airports around the world.
