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Related papers: Molecules in the early Universe

200 papers

Understanding the complex ionization structure and chemical composition of \hii\ regions poses a significant challenge in astrophysics. The abundance discrepancy problem, characterized by inconsistencies between abundances derived from…

The evolution of nonlinear density fluctuations around the Jeans mass shortly after cosmological recombination is analyzed using a 3D hydrodynamics/dark--matter code. The Cosmic Background Radiation (CBR) exerts Compton friction on free…

Astrophysics · Physics 2009-10-22 M. Umemura , A. Loeb , E. L. Turner

To constrain the universe before recombination (380000 years after the Big Bang), we mostly rely on the measurements of the primordial abundances that indicate the first insight into the thermal history of the universe. The first production…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-30 Tahani Makki , Mounib El Eid , Grant Mathews

The uncertainties which still plague our understanding of the evolution of the light nuclides D, 3He and 4He in the Galaxy are described. Measurements of the local abundance of deuterium range over a factor of 3. The observed dispersion can…

Astrophysics of Galaxies · Physics 2015-05-14 Donatella Romano

Reionization represents an important phase in the history of our Universe when ultraviolet radiation from the first luminous sources, primarily stars and accreting black holes, ionized the neutral hydrogen atoms in the intergalactic medium…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-18 Anirban Chakraborty , Tirthankar Roy Choudhury

Much of what we know about molecular clouds, and by extension star formation, comes from molecular line observations. Interpreting these correctly requires knowledge of the underlying molecular abundances. Simulations of molecular clouds…

Astrophysics of Galaxies · Physics 2023-08-02 F. D. Priestley , P. C. Clark , S. C. O. Glover , S. E. Ragan , O. Fehér , L. R. Prole , R. S. Klessen

We solve the recombination equation by taking into account the induced recombinations and a physical cut off in the hydrogen spectrum. The effective recombination coefficient is parametrized as a function of temperature and free electron…

Astrophysics · Physics 2008-02-03 Peter Boschan , Peter Biltzinger

We developed a three-dimensional 2-level hierarchical cosmological code with a realistic and robust treatment of multi-species non-equilibrium ionization and radiative cooling processes, and use it to investigate primordial star forming…

Astrophysics · Physics 2009-10-28 Yu Zhang , Michael L. Norman , Peter Anninos , Tom Abel

An introductory review of the early evolution of the Universe relevant to the primordial synthesis of the light nuclides deuterium, helium-3, helium-4 and lithium-7. The predictions of the element abundances in the "standard", hot, big bang…

Astrophysics · Physics 2009-10-31 Gary Steigman

Cosmology is nowadays going through a true revolution in the quantity and quality of observations that are capable of providing crucial information about the origin and evolution of the universe. In the first years of the next millenium we…

Astrophysics · Physics 2015-06-24 Juan Garcia-Bellido

The transformation of atomic hydrogen to molecular hydrogen through three-body reactions is a crucial stage in the collapse of primordial, metal-free halos, where the first generation of stars (Population III stars) in the Universe are…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Matthew J. Turk , Paul Clark , S. C. O. Glover , T. H. Greif , Tom Abel , Ralf Klessen , Volker Bromm

We discuss how measurements of fluctuations in the absorption of cosmic microwave background (CMB) photons by neutral gas during the cosmic dark ages, at redshifts z ~ 7--200, could reveal the primordial deuterium abundance of the Universe.…

Astrophysics · Physics 2007-05-23 Kris Sigurdson , Steven R. Furlanetto

Cosmic reionization is expected to be complex, extended and very inhomogeneous. Existing constraints at z~6 on the volume-averaged neutral hydrogen fraction, <x_HI>, are highly model-dependent and controversial. Constraints at z<6,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Ian D. McGreer , Andrei Mesinger , Xiaohui Fan

In this paper we discuss the possible distortions of the ionization history of the universe caused by an injection of non-thermal energy due to decays of hypothetical Super Heavy Dark Matter (SHDM) particles. These particles are usually…

Astrophysics · Physics 2009-11-07 A. G. Doroshkevich , P. D. Naselsky

When, and how, did the first galaxies and supermassive black holes (SMBH) form, and how did they reionization the Universe? First galaxy formation and cosmic reionization are among the last frontiers in studies of cosmic structure…

The observable universe is fundamentally inhomogeneous and anisotropic. Quantum description of the generation of these inhomogeneities and anisotropies is ill-understood and unsatisfactory. After providing a brief account of the standard…

General Relativity and Quantum Cosmology · Physics 2024-04-05 Sujoy K. Modak

After cosmic inflation, the universe is cold and almost empty. Thus, the inflation field should decay to the particles for BBN through the so-called reheating process. Later, the matter-antimatter asymmetry and dark matter are produced. In…

High Energy Physics - Phenomenology · Physics 2025-01-28 Fa Peng Huang

A possible way of detecting the first structure formation in a non-standard BBN Universe during the dark age, due to the resonant scattering of the CMBR photons in the rotational lines of the primordial CH molecule is discussed. The…

Astrophysics · Physics 2007-05-23 A. Lipovka , J. Saucedo , N. M. Lipovka

We present new calculations of the inhomogeneous process of cosmological reionization by carefully following the radiative transfer in pre-computed hydrodynamical simulations of galaxy formation. These new computations represent an…

Astrophysics · Physics 2009-11-07 Alexei O. Razoumov , Michael L. Norman , Tom Abel , Douglas Scott

The evolution of the Universe is the ultimate laboratory to study fundamental physics across energy scales that span about 25 orders of magnitude: from the grand unification scale through particle and nuclear physics scales down to the…

High Energy Physics - Phenomenology · Physics 2008-11-26 D. Boyanovsky , H. J. de Vega , D. J. Schwarz