5.1 Collapse scenario
Update
The first generation of stars to form in the early universe are known as Population III stars (formed at
redshifts
). Theoretical and computational evidence suggests that Population III stars may have
had masses
[2
, 1
, 96
]. Since these massive stars contained no metals, it was possible for them
to form directly and then evolve with very low stellar winds and thus very little mass loss. If the mass of a
nonrotating Population III star is
, its fate is to collapse directly to a black hole at the end of
its life [96
]. If rotational support prevents the star from direct collapse to a black hole, explosive
thermonuclear burning will cause the star to undergo a giant hypernova explosion. Prior to black
hole formation, the rotating, collapsed core will have a mass of
and a radius of
. Note that because these massive stars evolve so quickly (in a few million
years [10]), the events associated with their deaths will take place at roughly the redshifts of their
births.