AST-1A Lecture Notes - Lecture 31: Red Supergiant Star, Helium Flash, Degenerate Matter
Document Summary
Early stages are similar to the suns life but they proceed much faster. Form out of a cloud fragment that gravity forces to contract into a protostar. Gravity compresses hydrogen core making it possible for protons to slam into. 4 hydrogen nuclei fuse into 1 helium 4 nucleus (much more rapidly than carbon, oxygen or nitrogen resulting in the cno cycle. Fusion of heavier nuclei becoming a red supergiant (oxygen, neon, magnesium, and so on) Raising core temperature fusing helium into carbon with no helium flash. Carbon core shrinks as pressure, temp and density rise. Stars life track zigzags across the top of the h-r diagram progressing toward. Helium-capture reactions: when a helium nucleus fuses into another nucleus. Not possible to generate any kind of nuclear energy. Elements heavier than iron generate nuclear energy only through fission into lighter. Has the lowest mass per nuclear particle of all nuclei and cannot release energy no.
