Determination of CME masses from the analysis of EUV dimmings

LÓPEZ, FERMANDO M.; NUEVO, FEDERICO A.; CREMADES, HEBE ; VÁSQUEZ, ALBERTO M.; BALMACEDA, LAURA

Ciudad de Buenos Aires

Conferencia; COLAGE XI; 2018

ALAGE

Coronal mass ejections (CMEs) are one of the most spectacular transient events that can be observed in the solar atmosphere. Under certain conditions these events can perturb the terrestrial magnetosphere, producing intense geomagnetic storms. For this reason, a more accurate determination 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 massloss from the dimmings was obtained applying a Differential Emission Measure (DEM) technique on data obtained by the Atmospheric Imaging Assembly onboard the Solar Dynamics Observatory. The mass of the associated CMEs is determined from white-light images by the coronagraph COR2 onboard the Solar-Terrestrial Relations Observatory. By combiningboth 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.