The kink in the re vs T profile is the reason why some material glow red hot when heated. Note that it is when the electron returns to a higher orbit that the quantum is released and the material cools and glows. When the heat is continually applied, the material is seen to be glowing because the electrons are in SHM about the kink point. Some electrons are on their return lag of their SHM paths to higher orbit and emit quanta of energy as they pass over the kink. Their mean orbits still decrease with increasing temperature, T.
If not for SHM, the material will not glow when heat is applied. The electrons will move to lower orbit continuously as T increases. Only when the heat is remove and the material cools, do the electrons return to higher orbit over the kink, that packets of energy are emitted. With SHM the material glows when heated continuously. Visual evidence of SHM.
With increasing T, re decreases and eventually the lower electrons crush into the nucleus and you have matter/antimatter annihilation resulting in plasma and a huge amount of heat. Because of this huge amount of heat released, still more electrons drop to a lower orbit and crush into the nucleus as T increases further. A run away, escalating situation. The plasma may sustain itself without further heat input until all the material are exhausted. Light my fire!
