Derivation of the downward velocity of the flaring region of 26 June 1999

摘要

In the present study, three methods have been used to compute the downward velocity of the flare plasma of the solar flare on June 26, 1999. The first method is used to determine the plasma velocity of the studied flare from the Hα line asymmetries by using the asymmetry method developed by Edward (2009). The second one is to obtain the downward velocity of the flare plasma from the far wings of the excess profiles by the bisector method. This method was employed by; for example, Ichimoto and Kurokawa (1984), Falchi et al. (1992), and Ding et al. (1995). The third method is the modified cloud model which is described by Liu and Ding (2001a,b), Gu and Ding (2002), Semeida et al. (2004) and Berlicki (2007).