CME 3D-parameters Inversion by Cone Model

CME can affect the near-earth space environment and cause a geomagnetic disturbance. Therefore, it is of great application significance to predict whether and when it can reach the earth. Due to the limitation of observation ability, 3D-parameters are usually obtained by using cone model fitting according to the coronagraph projection observation information of CME near the sun, and then the effectiveness on earth of CME can be predicted by empirical prediction or interplanetary propagation process simulation. In the process of fitting, coronagraph observation data at different times can be taken as input, or CME can be restricted to occur near flares for fitting, which may result in completely different CME 3D-parameters, thus seriously affecting CME propagation prediction results. This paper selects a full halo CME event and a partial halo CME event, analyzes the changes of CME 3D parameter fitting results caused by different data input and fitting methods, and evaluates their impact on CME propagation prediction. The study found that the 3D-parameters of CME obtained by different data sources and fitting methods were significantly different, which affected the prediction of the ground validity of CME. In the future, it is necessary to evaluate the input data adopted and the fitting method, so as to predict the effects on earth of CME more accurately.