Trend of photospheric magnetic helicity flux in active regions generating halo coronal mass ejections

Context. Coronal mass ejections (CMEs) are very energetic events (similar to 10(32) erg) initiated in the solar atmosphere, resulting in the expulsion of magnetized plasma clouds that propagate into interplanetary space. It has been proposed that CMEs can play an important role in shedding magnetic helicity, avoiding its endless accumulation in the corona.status: publishe