English
Related papers

Related papers: Suppression of H_2 Cooling in the Ultraviolet Back…

200 papers

The first, self-consistent calculations are presented of the cosmological, H2-dissociating UV background produced during the epoch of reionization by the sources of reionization. Large-scale radiative transfer simulations of reionization…

Astrophysics · Physics 2015-05-13 Kyungjin Ahn , Paul R. Shapiro , Ilian T. Iliev , Garrelt Mellema , Ue-Li Pen

We use the hydrodynamic, cosmological EAGLE simulations to investigate how hot gas in haloes condenses to form and grow galaxies. We select haloes from the simulations that are actively cooling and study the temperature, distribution, and…

In this review we outline the major points of ab-initio cosmological models focusing on some galaxy evolution unresolved problems. In particular our knowledge of the star formation rate which leads galaxy evolution, i.e. luminosity, colors…

Astrophysics · Physics 2009-09-29 Paola Mazzei

We investigate the thermal and dynamical evolution of primordial gas clouds in the universe after decoupling. Comparing the time-scale of dynamical evolution with that of fragmentation, we can estimate the typical fragmentation scale. We…

Astrophysics · Physics 2009-10-31 Ryoichi Nishi , Hajime Susa , Hideya Uehara , Masako Yamada , Kazuyuki Omukai

Theoretical studies of structure formation find an inverse proportionality between the concentration of dark matter haloes and virial mass. This trend has been recently confirmed for virial masses Mvir > ~6e12 Msun by the observation of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Dominik Leier , Ignacio Ferreras , Prasenjit Saha

Within the precise cosmological framework provided by the Lambda-Cold Dark Matter model and standard Big Bang nucleosynthesis, the chemical evolution of the pregalactic gas can now be followed with accuracy limited only by the uncertainties…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Daniele Galli , Francesco Palla

We use a high-resolution $N$-body simulation to study how the formation of cold dark matter (CDM) halos is affected by their environments, and how such environmental effects produce the age-dependence of halo clustering observed in recent…

Astrophysics · Physics 2008-11-26 H. Y. Wang , H. J. Mo , Y. P. Jing

The H atoms inside minihalos (i.e. halos with virial temperatures T_vir < 10^4 K, in the mass range roughly from 10^4 M_sun to 10^8 M_sun) during the cosmic dark ages in a LambdaCDM universe produce a redshifted background 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…

Astrophysics · Physics 2007-05-23 Piero Madau

We review the relevance of H2 molecules for structure formation in cosmology. Molecules are important at high redshifts, when the first collapsed structures appear with typical temperatures of a few hundred Kelvin. In these chemically…

Astrophysics · Physics 2007-05-23 Tom Abel , Zoltan Haiman

The early universe hosted a large population of low-mass virialized "minihalos," that were not massive enough to form stars on their own. While most minihalos were photoevaporated by ionizing photons from star-forming galaxies, these…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 William J Gray , Evan Scannapieco

Population III stars are possible precursors to early massive and supermassive black holes (BHs). The presence of soft UV Lyman Werner (LW) background radiation can suppress Population III star formation in minihalos and allow them to form…

Astrophysics of Galaxies · Physics 2025-08-28 James Sullivan , Zoltan Haiman , Mihir Kulkarni , Eli Visbal

We present one-dimensional models of the hot gas in dark-matter halos, which both predict the existence of cool cores and explain their structure. Our models are directly applicable to semi-analytic models (SAMs) of galaxy formation. We…

Astrophysics of Galaxies · Physics 2015-06-05 Prateek Sharma , Michael McCourt , Ian J. Parrish , Eliot Quataert

We use zoom-in, hydrodynamical, cosmological $N$-body simulations tracing the formation of the first stellar clumps from the SImulating the Environments where Globular clusters Emerged (SIEGE) project, to study key structural properties of…

Astrophysics of Galaxies · Physics 2023-09-06 R. Pascale , F. Calura , A. Lupi , J. Rosdahl , E. Lacchin , M. Meneghetti , C. Nipoti , E. Vanzella , E. Vesperini , A. Zanella

We present a CSO and BIMA molecular line survey of the dense, quiescent molecular environment ahead of HH2. The molecular gas is cold, 13 K, and moderately dense, 3x10^5 cm^-3. A total of 14 species has been detected (including different…

Astrophysics · Physics 2009-11-07 J. M. Girart , S. Viti , D. A. Williams , R. Estalella , P. T. P Ho

The origin of rovibrational H_2 emission in the central galaxies of cooling flow clusters is poorly understood. Here we address this issue using data from our near-infrared spectroscopic survey of 32 of the most line luminous such systems,…

Astrophysics · Physics 2009-09-17 R. J. Wilman , A. C. Edge , R. M. Johnstone , A. C. Fabian , S. W. Allen , C. S. Crawford

The pancake collapse of pregalactic clouds under UV background radiation is explored with a one-dimensional sheet model. Here, attention is concentrated on elucidating the basic physics on the thermal evolution of pregalactic clouds exposed…

Astrophysics · Physics 2009-10-31 Hajime Susa , Masayuki Umemura

Molecular hydrogen is quite underabundant in damped Lyman-alpha systems at high redshift, when compared to the interstellar medium near the Sun. This has been interpreted as implying that the gas in damped Lyman-alpha systems is warm. like…

Astrophysics · Physics 2009-11-07 H. Liszt

The emission in the hyperfine structure 21 cm line of atomic hydrogen arising in the halos with masses $\sim10^6-10^{10}$ M$_\odot$ from the Dark Ages in the models with Warm Dark Matter (WDM) is analysed. The halos are assumed to be formed…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-25 B. Novosyadlyj , V. Shulga , Yu. Kulinich , W. Han

A defining prediction of the cold dark matter (CDM) cosmological model is the existence of a very large population of low-mass haloes. This population is absent in models in which the dark matter particle is warm (WDM). These alternatives…