English
Related papers

Related papers: Cosmic Reionization On Computers III. The Clumping…

200 papers

We compare the results from several sets of cosmological simulations of cosmic reionization, produced under Cosmic Reionization On Computers (CROC) project, with existing observational data on the high-redshift Ly-alpha forest and the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Nickolay Y. Gnedin , Alexander A. Kaurov

We investigate the properties of cosmological ionization fronts during the Epoch of Reionization using the CROC simulations. By analyzing reionization timing maps, we characterize ionization front velocities and curvatures and their…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-29 Hanjue Zhu , Nickolay Y. Gnedin

The incorporation of radiative transfer effects into cosmological hydrodynamical simulations is essential for understanding how the intergalactic medium (IGM) makes the transition from a neutral medium to one that is almost fully ionized.…

Astrophysics · Physics 2009-11-06 Aaron Sokasian , Tom Abel , Lars E. Hernquist

Lyman limit systems (LLSs) are dense hydrogen clouds with high enough HI column densities to absorb Lyman continuum photons emitted from distant quasars. Their high column densities imply an origin in dense environments; however, the…

Astrophysics of Galaxies · Physics 2024-03-04 Jiawen Fan , Hanjue Zhu , Camille Avestruz , Nickolay Y. Gnedin

We use cosmological simulations to explore the large-scale effects of reionization. Since reionization is a process that involves a large dynamic range - from galaxies to rare bright quasars - we need to be able to cover a significant…

Astrophysics · Physics 2008-11-26 Katharina Kohler , Nickolay Y. Gnedin , Andrew J. S. Hamilton

We explore the connection between the stellar component of galaxies and their host halos during the epoch of reionization ($5 \leq z\leq10$) using the CROC (Cosmic Reionization on Computers) simulations. We compare simulated galaxies with…

Astrophysics of Galaxies · Physics 2021-04-20 Hanjue Zhu , Camille Avestruz , Nickolay Y. Gnedin

Many recent models consider the structure of individual interstellar medium (ISM) clouds as a way to explain observations of large parts of galaxies. To compare such models to observations, one must understand how to translate between…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Adam K. Leroy , Cheoljong Lee , Andreas Schruba , Alberto Bolatto , Annie Hughes , Jerome Pety , Karin Sandstrom , Eva Schinnerer , Fabian Walter

Quasar absorption lines provide a unique window to the relationship between galaxies and the intergalactic medium during the Epoch of Reionization. In particular, high redshift quasars enable measurements of the neutral hydrogen content of…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-17 Ella Werre , David Robinson , Camille Avestruz , Nickolay Y. Gnedin

The reconstruction of galaxy cluster's gas density profiles is usually performed by assuming spherical symmetry and averaging the observed X-ray emission in circular annuli. In the case of a very inhomogeneous and asymmetric gas…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-15 D. Eckert , M. Roncarelli , S. Ettori , S. Molendi , F. Vazza , F. Gastaldello , M. Rossetti

In this first of several application papers, we investigate the mechanics of reionization from stellar sources in high-z galaxies, the utility of various clumping factors on estimating the recombination time in the IGM, and the photon…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Geoffrey C. So , Michael L. Norman , Daniel R. Reynolds , Robert P. Harkness

We present the first large-scale radiative transfer simulations of cosmic reionization, in a simulation volume of (100/h Mpc)^3, while at the same time capturing the dwarf galaxies which are primarily responsible for reionization. We…

The intergalactic medium is expected to clump on scales down to $10^4-10^8$ M$_{\odot}$ before the onset of reionization. The impact of these small-scale structures on reionization is poorly understood despite the modern understanding that…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-09 Anson D'Aloisio , Matthew McQuinn , Hy Trac , Christopher Cain , Andrei Mesinger

X-ray observations of galaxy clusters potentially provide powerful cosmological probes if systematics due to our incomplete knowledge of the intracluster medium (ICM) physics are understood and controlled. In this paper, we present mock…

Astrophysics · Physics 2008-11-26 Daisuke Nagai , Alexey Vikhlinin , Andrey V. Kravtsov

Large-scale reionization simulations are described which combine the results of cosmological N-body simulations that model the evolving density and velocity fields and identify the galactic halo sources, with ray-tracing radiative transfer…

We explore the mean and fluctuating redshifted 21 cm signal in numerical simulations of cosmic reionization from the Cosmic Reionization On Computers (CROC) project. We find that the mean signal varies between about $\pm20\rm{mK}$. Most…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-29 Alexander A. Kaurov , Nickolay Y. Gnedin

A model of the density distribution in the intergalactic medium, motivated by that found in numerical simulations, is used to demonstrate the effect of a clumpy IGM and discrete sources on the reionization of the universe. In an…

Astrophysics · Physics 2009-10-31 Jordi Miralda-Escude , Martin Haehnelt , Martin J. Rees

The propagation of cosmological ionization fronts during the reionization of the universe is strongly influenced by small-scale gas inhomogeneities due to structure formation. These inhomogeneities include both collapsed minihalos, which…

Astrophysics · Physics 2009-11-10 Ilian T. Iliev , Evan Scannapieco , Paul R. Shapiro

It has been hypothesized that photons from young, massive star clusters are responsible for maintaining the ionization of diffuse warm ionized gas seen in both the Milky Way and other disk galaxies. For a theoretical investigation of the…

Astrophysics of Galaxies · Physics 2020-07-22 Erin Kado-Fong , Jeong-Gyu Kim , Eve C. Ostriker , Chang-Goo Kim

We present predictions for the reionization of the intergalactic medium by stars in high-redshift galaxies. We calculate ionizing luminosities of galaxies, including the effects of absorption by interstellar gas and dust on the escape…

Astrophysics · Physics 2009-10-31 A. J. Benson , Adi Nusser , Naoshi Sugiyama , C. G. Lacey

The contribution of stars in galaxies to cosmic reionisation depends on the star formation history in the Universe, the abundance of galaxies during reionisation, the escape fraction of ionising photons and the clumping factor of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Jan-Pieter Paardekooper , Sadegh Khochfar , Claudio Dalla Vecchia