Advancing Simulations of Solar Eruption Initiation by Coupling Flux Emergence with Shear Injection Under Realistic Magnetic Field Strengths

Solar eruptions are driven by the rapid release of free magnetic energy accumulated in the corona. While a recent simulation by Jiang et al. established a fundamental mechanism for eruption initiation, it was limited by unrealistically weak magnetic fields and the absence of flux emergence. We overcome these limitations by developing a hybrid boundary driven magnetohydrodynamic (MHD) simulation that couples flux emergence with shear injection under realistic magnetic field strengths. The Boris correction to the MHD equations is employed to enable the magnetic field to reach observational values (∼2000 G) in the plasma with typical coronal density. A hybrid electric field driving strategy is designed: the variation of the magnetic flux is controlled by an inductive electric field component, while shear and free energy are injected via a non-inductive part caused by photospheric rotational flows. The simulation encompasses the complete sequence from flux emergence to eruption, showing that the photospheric rotational flow progressively shears the emerging arcade, forming a sigmoidal structure above the polarity inversion line. Ultimately, a thin current sheet forms, where reconnection sets in, creating a rapidly expanding flux rope. This consistency with previous simulations confirms the robustness of the eruption mechanism under more realistic parameters.