Astronomy and Astrophysics – Astrophysics
Scientific paper
2006-03-14
Astronomy and Astrophysics
Astrophysics
158 pages, lecture notes for the SAAS-Fee Winter School, April 2006 (to be published by Springer Verlag); http://obswww.unige.
Scientific paper
The first dwarf galaxies, which constitute the building blocks of the collapsed objects we find today in the Universe, had formed hundreds of millions of years after the big bang. This pedagogical review describes the early growth of their small-amplitude seed fluctuations from the epoch of inflation through dark matter decoupling and matter-radiation equality, to the final collapse and fragmentation of the dark matter on all mass scales above \~10^{-4} solar masses. The condensation of baryons into halos in the mass range of ~10^5-10^{10} solar masses led to the formation of the first stars and the re-ionization of the cold hydrogen gas, left over from the big bang. The production of heavy elements by the first stars started the metal enrichment process that eventually led to the formation of rocky planets and life. A wide variety of instruments currently under design [including large-aperture infrared telescopes on the ground or in space (JWST), and low-frequency arrays for the detection of redshifted 21cm radiation], will establish better understanding of the first sources of light during an epoch in cosmic history that was largely unexplored so far. Numerical simulations of reionization are computationally challenging, as they require radiative transfer across large cosmological volumes as well as sufficently high resolution to identify the sources of the ionizing radiation. The technological challenges for observations and the computational challenges for numerical simulations, will motivate intense work in this field over the coming decade.
No associations
LandOfFree
First Light does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with First Light, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and First Light will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-704510