 After the star has fused the helium of its core , the carbon product fuses producing a hot core with an outer shell of fusing helium . The star then follows an evolutionary path called the asymptotic giant branch ( AGB ) that parallels the other described red giant phase , but with a higher luminosity . The more massive AGB stars may undergo a brief period of carbon fusion before the core becomes degenerate . 
 After the star <a href='been_done' title='1'><mark>has</mark></a> fused the helium of its core , the carbon product fuses producing a hot core with an outer shell of fusing helium . The star then <a href='uninflect' title='2'><mark>follows</mark></a> an evolutionary path called the asymptotic giant branch ( AGB ) <a href='null_relcl' title='3'><mark>that</mark></a><a href='uninflect' title='4'><mark>parallels</mark></a> the other described red giant phase , but with a higher luminosity . The more massive AGB stars may undergo a brief period of carbon fusion before the core <a href='uninflect' title='5'><mark>becomes</mark></a> degenerate . 
After da star done fused the helium of its core , the carbon product fuses producing a hot core w an outer shell of fusing helium . The star then follow an evolutionary path called the asymptotic giant branch ( AGB ) parallel the other described red giant phase , but witwitthigher luminosity . The more massive AGB stars may undergo a brief period of carbon fusion b4 the core become degenerate .