CME Masses at Solar Minimum

Gareth Lawrence

Abstract

Much has been learned from the LASCO data set about the spatial and temporal distributions of CMEs, and also about some key parameters such as their typical speeds and - sometimes - accelerations, and the plane-of-sky angles they subtend. Less is known about the masses involved - the excess mass carried away in these explosive events. We present the results of calculations of masses of all 'significant' - i.e., ~1e13g or greater - CMEs observed by LASCO in a period around the minimum period of solar cycle 23 spanning several months. The question of the proportion of solar wind mass flux contained in CMEs at solar minimum is addressed. We also analyse in detail the masses of CMEs observed during the high-cadence (~3 min) LASCO/C3 programme run in Jan. 1996.