Investigating the Coronal Mass Ejections associated with DH type-II radio bursts and solar flares during the ascending phase of the solar cycle 24

Abstract

We studied a set of 74 CMEs, with shedding the light on the halo-CMEs (HCMEs), that are associated with decametric – hectometric (DH) type-II radio bursts (1–16 MHz) and solar flares during the period 2008–2014. The events were classified into 3 groups (disk, intermediate, and limb events) based on their longitudinal distribution.We found that the events are mostly distributed around 15.32° and 15.97° at the northern and southern solar hemispheres, respectively. We found that there is a clear dependence between the longitude and the CME’s width, speed, acceleration, mass, and kinetic energy. For the CMEs’ widths, most of the events were HCMEs (∼62%), while the partial HCMEs comprised ∼35% and the rest of events were CMEs with widths less than 120°. For the CMEs’ speeds, masses, and kinetic energies, the mean values showed a direct proportionality with the longitude, in which the limb events had the highest speeds, the largest masses, and the highest kinetic energies. The mean peak flux of the solar flares for different longitudes was comparable, but the disk flares were more energetic. The intermediate flares were considered as gradual flares since they tended to last longer, while the limb flares were considered as impulsive flares since they tended to last shorter.A weak correlation (R = 0.32) between the kinetic energy of the CMEs and the duration of the associated flares has been noticed, while there was a good correlation (R = 0.76) between the kinetic energy of the CMEs and the peak flux of the associated flares. We found a fair correlation (R = 0.58) between the kinetic energy of the CMEs and the duration of the associated DH type-II radio bursts.