Astrophysics (index)about

red-giant branch

(a stage in the evolution of some smaller stars)

The term red-giant branch (RGB) is generally used for a grouping of stars on the H-R diagram that form a line on the diagram, leading away from the main sequence, and representing a phase just after the main sequence phase. It includes some of the red giants (i.e., very bright, reddish stars).

The stars have a helium core surrounded by hydrogen undergoing fusion, at a point when the helium is not burning. Spectrally, they are K-type star or M-type star, but much brighter than stars in those class during the main sequence, and often subgiants.

(star type,stellar evolution,H-R diagram)