Determination of CME masses from the analysis of EUV dimmings

F. M. LOPEZ; H. CREMADES; L. BALMACEDA; F. A. NUEVO; A. M. VÁSQUEZ

Buenos Aires

Congreso; XI COLAGE; 2018

Coronal mass ejections (CMEs) are one of the most spectacular transient events that can be observed in the solar atmosphere. They carry large amounts of plasma and magnetic fields from the low corona into the interplanetary medium. Under certain conditions these events can perturb the terrestrial magnetosphere, producing intense geomagnetic storms. For this reason, the study of fundamental parameters of CMEs, such as their mass, is crucial to estimate their impact on our planet. Unfortunately, the determination of CME masses when the events propagate along the observer?s line-of-sight involve large errors, both due to the nature of the Thomson scattering effect and to the lack of knowledge of the density distribution within real CMEs. In this work, we analyzed 32 dimming events for which we determined the temporal evolution of the mass loss, as well as the evolution of the mass of the associated CMEs. The mass loss from the dimmings was obtained applying a Differential Measure Technique (DEM) on data obtained by the Atmospheric Imaging Assembly onboard the Solar Dynamics Observatory. The mass of the associated CMEs is determined from images by thecoronagraph COR2 onboard the Solar-Terrestrial Relations Observatory. By combining both analyses, we developed a method to estimate the evolution of the mass of CMEs as a function of height. This method is solely based on the determined EUV evacuated masses, and does not rely on white-light coronagraphic data. To evaluate the success of our method, the results are contrasted against the mass of CMEs measured on quadrature images from COR2.