Speaker
Description
The Fermi Large Area Telescope regularly observes continuous emission of gamma rays from the Sun. Gamma rays from the non-flaring Sun are produced by continuous bombardment of Galactic cosmic rays. By using 14 years of Fermi LAT data above 5 GeV, we study the morphology of the solar emission and how the high-energy photons are distributed in the solar disk in time over the solar cycle. This work unveils compelling evidence of asymmetric GeV emission from the solar disk. We found that the most significant asymmetry is observed around June 2014. This period coincides with the solar polar magnetic field reversal during the solar maximum, which happens once in a decade. This is the first time that some temporal dependence with the magnetic field conditions has been observed. Notably, current theoretical expectations do not account for such an asymmetry, adding another mystery to our closest star and opening up new and exciting directions for studying the Sun.