DETECTING THE RISE AND FALL OF THE FIRST STARS BY THEIR IMPACT ON COSMIC REIONIZATION
- Department of Earth Sciences, Chosun University, Gwangju 501-759 (Korea, Republic of)
- Astronomy Centre, Department of Physics and Astronomy, Pevensey II Building, University of Sussex, Falmer, Brighton BN1 9QH (United Kingdom)
- Department of Astronomy and Texas Cosmology Center, University of Texas, Austin, TX 78712-1083 (United States)
- Department of Astronomy and Oskar Klein Centre, Stockholm University, Albanova, SE-10691 Stockholm (Sweden)
- Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, Victoria 3122 (Australia)
The intergalactic medium was reionized before redshift z {approx} 6, most likely by starlight which escaped from early galaxies. The very first stars formed when hydrogen molecules (H{sub 2}) cooled gas inside the smallest galaxies, minihalos (MHs) of mass between 10{sup 5} and 10{sup 8} M{sub Sun }. Although the very first stars began forming inside these MHs before redshift z {approx} 40, their contribution has, to date, been ignored in large-scale simulations of this cosmic reionization. Here we report results from the first reionization simulations to include these first stars and the radiative feedback that limited their formation, in a volume large enough to follow the crucial spatial variations that influenced the process and its observability. We show that, while MH stars stopped far short of fully ionizing the universe, reionization began much earlier with MH sources than without, and was greatly extended, which boosts the intergalactic electron-scattering optical depth and the large-angle polarization fluctuations of the cosmic microwave background significantly. This boost should be readily detectable by Planck, although within current Wilkinson Microwave Anisotropy Probe uncertainties. If reionization ended as late as z{sub ov} {approx}< 7, as suggested by other observations, Planck will thereby see the signature of the first stars at high redshift, currently undetectable by other probes.
- OSTI ID:
- 22078572
- Journal Information:
- Astrophysical Journal Letters, Vol. 756, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 2041-8205
- Country of Publication:
- United States
- Language:
- English
Similar Records
Dark stars: Implications and constraints from cosmic reionization and extragalactic background radiation
Extragalactic background light from hierarchical galaxy formation. Gamma-ray attenuation up to the epoch of cosmic reionization and the first stars