相关论文: Feedback from the IR Background in the Early Unive…
Feedback to the interstellar medium (ISM) from ionising radiation, stellar winds and supernovae is central to regulating star formation in galaxies. Due to their low mass ($M_{*} < 10^{9}$\,M$_\odot$), dwarf galaxies are particularly…
We present numerical simulations of how a 120 M$_\odot$ primordial star regulates star formation in nearby cosmological halos at $z \sim$ 20 by photoevaporation. Our models include nine-species primordial chemistry and self-consistent…
Feedback effects due to massive stars and supernovae in the first objects are shown to strongly regulate both galaxy formation/evolution and the reionization process. Here we review the most important ones in some detail. We discuss how…
We investigate the process of metal-free star formation in the first galaxies with a high-resolution cosmological simulation. We consider the cosmologically motivated scenario in which a strong molecule-destroying Lyman-Werner (LW)…
We describe how star formation is expected to proceed in the early metal-free Universe, focusing on the very first generations of stars. We then discuss how the star formation process may change as the effects of metallicity, external…
From studying the cosmic microwave background, we know our Universe started out very simple. It was by and large homogeneous and isotropic, with small fluctuations that can be described by linear perturbation theory. In stark contrast, the…
The formation of the first stars is an exciting frontier area in astronomy. Early redshifts z ~ 20 have become observationally promising as a result of a recently recognized effect of a supersonic relative velocity between the dark matter…
The character of the first galaxies at redshifts z > 10 strongly depends on their level of pre-enrichment, which is in turn determined by the rate of primordial star formation prior to their assembly. In order for the first galaxies to…
In popular cold dark matter cosmological scenarios, stars may have first appeared in significant numbers around a redshift of 10 or so, as the gas within protogalactic halos with virial temperatures in excess of 20,000 K (corresponding to…
It is well established that between 380000 and 1 billion years after the Big Bang the Inter Galactic Medium (IGM) underwent a "phase transformation" from cold and fully neutral to warm (~10^4 K) and ionized. Whether this phase…
There has been remarkable progress recently in both observational and theoretical studies of galaxy formation and evolution. Largely due to a combination of deep Hubble Space Telescope imaging, Keck spectroscopy, and COBE far-IR background…
We review recent theoretical results on the formation of the first stars and quasars in the universe, and emphasize related open questions. In particular, we list important differences between the star formation process at high redshifts…
Probing the growth of structure from the epoch of hydrogen recombination to the formation of the first stars and galaxies is one of the most important uncharted areas of observational cosmology. Far-IR spectroscopy covering $\lambda$…
The first galaxies forming a few hundred million years after the Big Bang are the key drivers of cosmic evolution and ideal laboratories to study theories of galaxy formation. We here study the role of UV radiation in suppressing star…
We study how the first galaxies were assembled under feedback from the accretion onto a central black hole (BH) that is left behind by the first generation of metal-free stars through self-consistent, cosmological simulations. X-ray…
Dark stars powered by dark matter annihilation have been proposed as the first luminous sources in the universe. These stars are believed to form in the central dark matter cusp of low-mass minihalos. Recent calculations indicate stellar…
Massive stars produce copious quantities of ultraviolet radiation beyond the Lyman limit, photoionizing the interstellar medium (ISM) and producing H II regions. As strong sources of recombination- and forbidden-line emission, infrared…
We describe results from a fully self-consistent three dimensional hydrodynamical simulation of the formation of one of the first stars in the Universe. Dark matter dominated pre-galactic objects form because of gravitational instability…
Using a reliably measured intrinsic (i.e. corrected for absorption effects) present-day luminosity function of high-mass X-ray binaries (HMXBs) in the 0.25-2 keV energy band per unit star-formation rate, we estimate the preheating of the…
The formation of the first generations of stars at redshifts z > 15-20 signaled the transition from the simple initial state of the universe to one of increasing complexity. We here review recent progress in understanding the assembly…