8
Motion in the
HR Diagram
•During
H core burning (main sequence)
–L
increases slowly as He accumulates in the core (and TCore increases)
•During
H shell burning
–At
first R increases, T decreases
–L
then increases slowly as more He accumulates in core (and TCore increases)
–Eventually
He ignites in the
core
From our text: Horizons, by Seeds