Study on The Prediction Method of Characteristic Parameters of Solar X-ray Flares

Solar flares are important events for the space weather. The predic- tion of relevant parameters of solar flares has practical significance for evaluating the effect of sudden ionospheric disturbance (SID). The data of soft X-ray flux observed by the GOES-8 satellite in the 23th solar cycle are used to predict the peak intensities and ending times of X-class flares with the method of data fit- ting. Using this method to analyze the X-class flares in the 23th solar cycle, it is possible to predict the peak flux of an X-class flare 17 minutes in advance at most. And the ending time of an X-class flare may be predicted about 60 minutes in advance at most. The predicted results indicate that the prediction method has certain effectiveness and applicability.