Speaker
Description
First Name: Juxhin
Last Name: Zhuleku
Affiliation: University of Ioannina
All Authors: Vasilis Archontis, Kostas Moraitis
Abstract: Active regions on the Sun are produced by magnetic flux tubes emerging from the solar interior to the surface. Previous numerical models based on cylindrical tubes led to sunspots drifting apart for large distances, contradicting observations of sunspots with fixed distance over time. To address this discrepancy, we present results from 3D MHD simulations investigating the emergence of toroidal flux tubes with feet anchored at the base of the numerical box. This approach ensures that the emerging spots will drift apart up to a certain fixed point. Using the Lare3D code, we numerically solve the 3D time-dependent compressible, resistive MHD equations in Cartesian coordinates. Our simulations span from the convection zone to the corona, with a plane parallel stratification of the solar interior and atmosphere. We initiate the simulations with a toroidal magnetic flux tube at the bottom of the convection zone and let it rise buoyantly to the surface. We consider cases with and without the inclusion of a pre-existing ambient magnetic field. Our results show a recurrent formation and eruption of multiple flux ropes. We calculated the free energy and relative helicity in the atmosphere and we found that both quantities decrease in magnitude during the eruptive events and build again afterwards maintaining the recurrent cycle of eruptions which continues even after the end of the flux emergence phase. Finally by using the temperature response function of the EUI instrument on board Solar Orbiter, we synthesize the emission of those eruptive events which can be compared with observations of jets and coronal mass ejections.