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Analysis of a database of solar coronal mass ejections (CMEs) and associatedflares over the period 1996-2007 finds well-behaved power law relationshipsbetween the 1-8 AA flare X-ray fluence and CME mass and kinetic energy. Weextrapolate these relationships to lower and higher flare energies to estimatethe mass and energy loss due to CMEs from stellar coronae, assuming that theobserved X-ray emission of the latter is dominated by flares with a frequencyas a function of energy dn/dE=kE^-alpha. For solar-like stars at saturatedlevels of X-ray activity, the implied losses depend fairly weakly on theassumed value of alpha and are very large: M_dot ~ 5x10^-10 M_sun/yr and E_dot~ 0.1L_sun. In order to avoid such large energy requirements, either therelationships between CME mass and speed and flare energy must flatten forX-ray fluence >~ 10^31 erg, or the flare-CME association must dropsignificantly below 1 for more energetic events. If active coronae aredominated by flares, then the total coronal energy budget is likely to be up toan order of magnitude larger than the canonical 10^-3 L_bol X-ray saturationthreshold. This raises the question of what is the maximum energy a magneticdynamo can extract from a star? For an energy budget of 1% of L_bol, the CMEmass loss rate is about 5x10^-11 M_sun/yr.

Implications of mass and energy loss due to coronal mass ejections on magnetically-active stars