What are the primary drivers behind the intense mass ejection observed during the post-red giant phase?

Answer

Thermal pulsations and strong stellar winds

The transition phase makes the star highly unstable, resulting in strong thermal pulsations. These pulsations, combined with exceptionally powerful stellar winds, physically drive vast amounts of gas and dust away from the star's surface.

What are the primary drivers behind the intense mass ejection observed during the post-red giant phase?
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