Data-driven simulations of magnetic field evolution in Active Region 11429: Magneto-friction method using PENCIL code

Abstract

Coronal magnetic fields evolve quasi statically over long time scales and dynamically over short time scales. As of now there exists no regular measurements of coronal magnetic fields, and therefore generating the coronal magnetic field evolution using the observations of the magnetic field at the photosphere is of fundamental requirement to understand the origin of the transient phenomena from the solar active regions. Using the magnetofriction (MF) approach, we aim to simulate the coronal field evolution in the solar active region 11429. The MF method is implemented in open source \PC along with a driver module to drive the initial field with different boundary conditions prescribed from observed vector magnetic fields at the photosphere. In order to work with vector potential and the observations, we prescribe three types of bottom boundary drivers with varying free-magnetic energy. The MF simulation reproduces the magnetic structure which better matches to the sigmoidal morphology exhibited by AIA images at the pre-eruptive time. We found that the already sheared field further driven by the sheared magnetic field will maintain and further build the highly sheared coronal magnetic configuration such as seen in AR 11429. Data-driven MF simulation is a viable tool to generate the coronal magnetic field evolution capturing the formation of the twisted flux rope and its eruption.