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Xue-Shang Feng

Publications and source records attributed to Xue-Shang Feng.

2 recordsLinked to original sources

A New Approach of Data-driven Simulation and Its Application to Solar Active Region 12673

The solar coronal magnetic field is a pivotal element in the study of eruptive phenomena, and understanding its dynamic evolution has long been a focal point in solar physics. Numerical models, driven directly by observation data, serve as indispensable tools in investigating the dynamics of the coronal magnetic field. This paper presents a new approach to electric field inversion, which involves modifying the electric field derived from the DAVE4VM velocity field using ideal Ohm's law. The time series of the modified electric field is used as a boundary condition to drive a MHD model, which is applied to simulate the magnetic field evolution of active region 12673. The simulation results demonstrate that our method enhances the magnetic energy injection through the bottom boundary, as compared with energy injection calculated directly from the DAVE4VM code, and reproduce of the evolution of the photospheric magnetic flux. The coronal magnetic field structure is also in morphological similarity to the coronal loops. This new approach will be applied to the high-accuracy simulation of eruption phenomena and provide more details on the dynamical evolution of the coronal magnetic field.

astro-ph.SR

Two Time-dependent Solutions of Magnetic field Annihilation in Two Dimensions

In this paper, two classes of exact analytic time-dependent soultion of magnetic annihilation for incompressible magnetic fluid, have been obtained by solving the magnetohydrodynamic (MHD) equations directly. The solutions derived here possess scaling property with time $t$ as the scale factor. Based on these two solutions, we find that, for some given inflow fields, the evolution of the annihilating magnetic field can be described by the solutions of certain ordinary differential equations whose variables are dilated simply by time $t$. The relevant evolution characteristics in the process of magnetic annihilation are also revealed.

physics.plasm-ph