Abstract
Recently, two strong homologous white light flares of X-GOES class occurred
on the Sun on Sept. 06, 2017, providing a rare exceptional opportunity to study
the mechanisms responsible for the formation of the magnetic field
configurations suitable for the manifestation of such yet enigmatic eruptive
events and their effects in the lower layers of the solar atmosphere.
Using photospheric vector magnetograms, taken before the beginning of the two
X-class events, as boundary conditions to reconstruct the non$-$linear coronal
magnetic field configuration, we identified two related 3D null points located
at low heights above the photosphere (i.e. in very low corona). These null
points are most likely responsible for the triggering of the two strong X-GOES
class flares. We deduced that their formation at such low altitudes may
plausibly be ascribed to the peculiar photospheric horizontal motions of the
main magnetic structures of the hosting Active Region NOAA 12673.
These events can be adopted as a hint for a possible interpretation of the
activity of young G-type stars, recently reported by the Kepler mission. We
argued that a possible explanation of the acceleration of huge numbers of
particles producing white light emission, during the Sept. 6 events as well as
during white light flares in young Sun-like stars, might be attributed to the
special accompanying conditions of the occurrence of magnetic reconnection at
low altitudes of their atmospheres.