  We have proposed that the first phase of stellar evolution in the history of
the Universe may be Dark Stars (DS), powered by dark matter heating rather than
by nuclear fusion, and in this paper we examine the history of these DS. The
power source is annihilation of Weakly Interacting Massive Particles (WIMPs)
which are their own antiparticles. These WIMPs are the best motivated dark
matter (DM) candidates and may be discovered by ongoing direct or indirect
detection searches (e.g. FERMI /GLAST) or at the Large Hadron Collider at CERN.
A new stellar phase results, powered by DM annihilation as long as there is DM
fuel, from millions to billions of years. We build up the dark stars from the
time DM heating becomes the dominant power source, accreting more and more
matter onto them. We have included many new effects in the current study,
including a variety of particle masses and accretion rates, nuclear burning,
feedback mechanisms, and possible repopulation of DM density due to capture.
Remarkably, we find that in all these cases, we obtain the same result: the
first stars are very large, 500-1000 times as massive as the Sun; as well as
puffy (radii 1-10 A.U.), bright ($10^6-10^7 L_\odot$), and cool ($T_{surf} <
$10,000 K) during the accretion. These results differ markedly from the
standard picture in the absence of DM heating. Hence DS should be
observationally distinct from standard Pop III stars. In addition, DS avoid the
(unobserved) element enrichment produced by the standard first stars. Once the
dark matter fuel is exhausted, the DS becomes a heavy main sequence star; these
stars eventually collapse to form massive black holes that may provide seeds
for the supermassive black holes and intermediate black holes, and explain
ARCADE data.
