The Study Of The Magnetic Topology Structure In An Ephemeral Active Region And The Relationship Between Magnetic Flux Emergence And Solar Eruption

The aim of this paper is twofold, one is to pinpoint a process of magnetic flux emergence in an ephemeral active region (EAR), and another is to analyze the magnetic topology structure of this ephemeral active region. For the first part, we discuss the link between the magnetic flux emergence and soft x-ray eruption in other nearby solar active regions using data in both high temporal and spatial resolution from the Atmospheric Imaging Assembly (hereafter AIA) and Helioseismic and Magnetic Imager (hereafter HMI) onboard the Solar Dynamical Observatory (hereafter SDO). The observations from the AIA covers four radiation wavelengths in different altitude, and the radiation wavelength includes9.4nm,17.1nm,160nm and450nm. On the basis of these observational data, we carry out a comprehensive discuss and unearth that there is some internal interactions between our target EAR and active region NOAA11402. For the second part, we study the magnetic topology structure of the EAR discussed before by the help of the line-of-sight magnetic field intensity from the HMI. And we found there was a North-South bipolar field firstly and then another East-West emerging, finally, only the East-West one in the EAR. In this process, the magnetic structure of EAR became parallel to East-West direction, and its shear angle with the vicinal magnetic topology structure decreased gradually. So we infer that the rising of twisted flux rope resulted in the change of magnetic structure in the EAR.