post-main-sequence evolution of high-mass stars

(M/M_sun > 8 - 12 ?? )

lack of electron degeneracy allows burning beyond carbon

each time a fuel source runs out,

core contracts, raising the temperature,

until a new fuel source begins to burn

endothermic Fe reactions cool core: core implodes

which squeezes e + p ---> n + n_e
g   +  g  --->  n_i  +  n_i

some nuclei dissolve into neutrons
photodisintegration of other nuclei
formation of nuclei more massive than iron

inter-neutron nuclear forces (may) cause core to rebound,

(in which case a neutron star is formed)

generating an outward-bound shock

(alternative is formation of a black hole)

what blows off the envelope?

(if released energy > envelope gravitational binding energy)
radiation pressure of light from exothermic reactions in envelope?

the neutrinos?

the shock wave?

exterior effects of the supernova explosion

ejection of envelope

only fusion of nuclei heavier than iron/nickel

shock wave may initiate star formation elsewhere

interior of remnant may be lit by synchrotron radiation

cosmic rays accelerated by nebula may contribute to the origin of life or genetic mutation