AGB

Asymptotic giant branch

Stars powered by fusion of hydrogen and helium in shell with an inactive core of carbon and oxygen

The asymptotic giant branch (AGB) is a region of the Hertzsprung–Russell diagram populated by evolved cool luminous stars. This is a period of stellar evolution undertaken by all low- to intermediate-mass stars (about 0.5 to 8 solar masses) late in their lives.

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