κH-Mechanism of a Solar Eruption Produced Self-Consistently by Flux Emergence

Abstract

Abstract We report on a new magnetohydrodynamic simulation for the sequence evolution of a magnetic field from emergence to eruption on the Sun. The magnetic field in the shape of a twisted flux tube emerging below the solar surface forms a pre-eruptive structure in the corona, which is composed of expanding envelop flux and a quasi-static inner core called flux rope; this inner core eventually seems to erupt. The evolution proceeds self-consistently; that is, any preexisting coronal magnetic field that causes additional side effects on the evolution of the emerging magnetic field is not assumed. This highlights a possible eruption mechanism inherent in the dynamic nature of the emerging magnetic field. The mechanism is characterized by two key quantities: the curvature ($ \kappa$ ) and the scale height ($ H$ ) of the emerging magnetic field.