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k sub c 9x10^9
E(grav) -(3/5)((GM^2)/R)
E(KE) (3kT)/2
The elements created in the first three seconds after the big bang. H, He, Li, Be. After three seconds, the temperature becomes too low to break the coulomb barrier to make heavier elements. The heavier elements are made in the later stages of a stars lifetime.
Jeans Mass The critical mass for a gas cloud, which given a temperature and density, will cause the cloud to collapse under gravity.
Jeans Radius The critical radius for a gas cloud that will collapse under its own gravity.
Will a bigger or smaller star reach the main sequence first? The bigger stars both enter and exit the main sequence faster. Burn bright die young. This is because the bigger star has a higher core temperature and more potential energy.
Hydrostatic Equilibrium F(press) = F(grav)
Protostar Core collapse under gravity, core begins to heat up.
Main Sequence Burns hydrogen in helium in the p-p chain. Luminosity increases.
Red Giant Hydrogen fuel runs out. Core burning switches off, core contracts and heats up, becoming degenerate. Outer hydrogen shell ignites and the outer envelope expands and cools. Opacity changes, making the star more luminous.
Horizontal Branch Phase Helium burning core, hydrogen burning shell. Pulsations and stellar winds.
Planetary Nebula and White Dwarf Degenerate core.
Created by: zkeane