相关论文: The Dawn of Chemistry
We study the formation of first molecules, negative Hydrogen ions and molecular ions in model of the Universe with cosmological constant and cold dark matter. The cosmological recombination is described in the framework of modified model of…
The chemistry of the early Universe is a fascinating field of study. Even in the absence of any elements heavier than lithium, a surprising degree of chemical complexity proves to be possible, giving the topic considerable interest in its…
Primordial chemistry began, at the recombination epoch, when the adiabatic expansion caused the temperature of the radiation to fall below 4000K. The chemistry of the early Universe involves the elements hydrogen, its isotope deuterium,…
At early times the Universe was filled up with an extremely dense and hot gas. Due to the expansion it cooled below the binding energies of atoms which led to the formation of the first nuclei. In the physical environment of the…
Chemistry plays a particular role in astrophysics. After atomic hydrogen, helium and their ions, the Universe probably contains more mass in molecules than in any other species. Molecule formation in the early, pre-galactic Universe may…
The process of molecule formation in the primordial gas is considered in the framework of Friedmann cosmological models from redshift z=1e4 to z=0. First, a comprehensive analysis of 87 gas phase reaction rates (both collisional and…
Primordial chemistry began in the recombination epoch when the adiabatic expansion caused the temperature of the radiation to fall below 4000 K. The chemistry of the early Universe involves the elements hydrogen, its isotope deuterium,…
We study the formation and destruction of the first molecules at the epochs of the Dark Ages and Cosmic Dawn to evaluate the luminosity of the protogalaxy clumps (halos) in the molecular lines. The cosmological recombination is described…
The development of primordial inhomogeneities into the non-linear regime and the formation of the first astrophysical objects within dark matter halos mark the transition from a simple, neutral, cooling universe -- described by just a few…
Cosmic structure originated from minute density perturbations in an almost homogeneous universe. The first stars are believed to be very massive and luminous, providing the first ionizing radiation and heavy elements to the universe and…
The development of primordial inhomogeneities into the non-linear regime and the formation of the first bound objects mark the transition from a simple cooling universe -- described by just a few parameters -- to a very messy hot one -- the…
The "dark age" of the Universe is generally pointed out as the period between the recombination epoch and the horizon of current observations (z=5-6). The arrow of time in the cosmic history describes the progression from simplicity to…
Observations made using large ground-based and space-borne telescopes have probed cosmic history all the way from the present-day to a time when the Universe was less than a tenth of its present age. Earlier on lies the remaining frontier,…
It is now well known that a primordial chemistry, involving light elements produced during the nucleosynthesis period, might develop during the hydrogen post-recombination era. In particular, molecular ions and primordial molecules such as…
A prediction of standard inflationary cosmology is that the elemental composition of the medium out of which the earliest stars and galaxies condensed consisted primarily of hydrogen and helium 4He with small admixtures of deuterium,…
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 $\lambda$…
(abridged) We use large cosmological simulations to study the origin of primordial star-forming clouds in a Lambda CDM universe, by following the formation of dark matter halos and the cooling of gas within them. To model the physics of…
The Cosmic Dark Ages mark a pivotal era of the universe's evolution, transitioning from a neutral, opaque medium to the emergence of the first stars and galaxies that initiated cosmic reionization. This study examines the thermodynamics of…
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…
The emergence of the first sources of light at redshifts of z ~ 10-30 signaled the transition from the simple initial state of the Universe to one of increasing complexity. We review recent progress in our understanding of the formation of…