English
Related papers

Related papers: Ionization fronts and their interaction with densi…

200 papers

Full radiative transfer in 3D space has been solved to pursue the reionization history in an inhomogeneous universe. It has been shown that the reionization of an inhomogeneous universe is not a prompt event, but a fairly slow process.…

Astrophysics · Physics 2007-05-23 M. Umemura , T. Nakamoto , H. Susa

We investigate the possible effects of reionization by active sources on the cosmic microwave background. We concentrate on the sources themselves as the origin of reionization, rather than early object formation, introducing an extra…

Astrophysics · Physics 2010-04-08 Jochen Weller , Richard A. Battye , Andreas Albrecht

We simulate the evolution of a 10^9 Msun dark matter halo in a cosmological setting with an adaptive-mesh refinement code as an analogue to local low luminosity dwarf irregular and dwarf spheroidal galaxies. The primary goal of our study is…

We simulate a plausible cosmological model in considerable physical and numerical detail through the successive phases of reheating (at 10<z<20), formation of Pop III stars at z=15 (due to molecular hydrogen cooling), with subsequent…

Astrophysics · Physics 2009-10-28 Nickolay Y. Gnedin , Jeremiah P. Ostriker

The reionization of the second electron of helium shapes the physical state of intergalactic gas at redshifts between 2 < z < 5. Because performing full in situ radiative transfer in hydrodynamic simulations is computationally expensive for…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-22 Phoebe Upton Sanderbeck , Simeon Bird

A variety of observations now indicate that intergalactic helium was fully ionized by z~3. The most recent measurements of the high-redshift quasar luminosity function imply that these sources had produced ~2.5 ionizing photons per helium…

Astrophysics · Physics 2009-11-13 Steven Furlanetto , S. Peng Oh

The temporal evolution of the ionizing UV background radiation field at high redshift provides a probe of the evolution of the early star formation rate. By comparing the observed levels of absorption in the highest redshift quasar spectra…

Astrophysics · Physics 2009-11-07 Renyue Cen , Patrick McDonald

Secondary CMB anisotropies and polarization provide a laboratory to study structure formation in the reionized epoch. We consider the kinetic Sunyaev-Zel'dovich effect from mildly nonlinear large-scale structure and show that it is a…

Astrophysics · Physics 2009-10-31 Wayne Hu

Reducing the power on small scales relative to the `standard' LCDM model alleviates a number of possible discrepancies with observations, and is favored by the recent analysis of WMAP plus galaxy and Lyman-alpha forest data. Here, we…

Astrophysics · Physics 2008-11-26 Rachel S. Somerville , James S. Bullock , Mario Livio

One of the main challenges facing standard hierarchical structure formation models is that the predicted abundance of galactic subhalos with circular velocities of 10-30 km/s is an order of magnitude higher than the number of satellites…

Astrophysics · Physics 2009-10-31 James S. Bullock , Andrey V. Kravtsov , David H. Weinberg

Tseliakhovich & Hirata recently discovered that higher-order corrections to the cosmological linear-perturbation theory lead to supersonic coherent baryonic flows just after recombination (i.e. z~1020), with rms velocities of ~30 km/s…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Umberto Maio , Leon V. E. Koopmans , Benedetta Ciardi

Binary stars are abundant in nearby galaxies, but are typically unaccounted for in simulations of the high redshift Universe. Stellar population synthesis models that include the effects of binary evolution result in greater relative…

Astrophysics of Galaxies · Physics 2021-05-24 Caitlin C. Doughty , Kristian M. Finlator

During reionization, intergalactic ionization fronts (I-fronts) are sources of Ly$\alpha$ line radiation produced by collisional excitation of hydrogen atoms within the fronts. In principle, detecting this emission could provide direct…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-24 Bayu Wilson , Anson D'Aloisio , Christopher Cain , Eli Visbal , George D. Becker

The fluid forces associated with primordial magnetic fields (PMFs) generate small-scale fluctuations in the primordial density field, which add to the $\mathrm{\Lambda CDM}$ linear matter power spectrum on small scales. These enhanced…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-01 Hector Afonso G. Cruz , Tal Adi , Jordan Flitter , Marc Kamionkowski , Ely D. Kovetz

Small galaxies are thought to be the main contributors to the ionising budget of the Universe before reionisation was complete. There have been a number of numerical studies trying to quantify their ionising efficiency through the escape…

Astrophysics of Galaxies · Physics 2015-10-26 M. Trebitsch , J. Blaizot , J. Rosdahl

It is believed that the first star-forming galaxies are the main drivers of cosmic reionization. It is usually assumed that there is a one-to-one relationship between the star formation rate (SFR) inside a galaxy and the host halo mass in…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-26 Chandra Shekhar Murmu , Kanan K. Datta , Suman Majumdar , Thomas R. Greve

We present predictions for two statistical measures of the hydrogen reionization process at high redshift. The first statistic is the number of neutral segments identified in spectra of high redshift QSOs as a function of their length. The…

Astrophysics · Physics 2009-11-07 Adi Nusser , Andrew Benson , Naoshi Sugiyama , Cedric Lacey

We present numerical simulations of primordial supernovae in cosmological minihalos at $z \sim$ 20. We consider Type II supernovae, hypernovae, and pair instability supernovae (PISN) in halos from 6.9 $\times$ 10$^5$ - 1.2 $\times$ 10$^7$…

Astrophysics · Physics 2009-11-13 Daniel Whalen , Bob van Veelen , Brian W. O'Shea , Michael L. Norman

In the early universe, substantial relative "stream" velocities between the gas and dark matter arise due to radiation pressure and persist after recombination. To asses the impact of these velocities on high-redshift structure formation,…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-28 Mark L. A. Richardson , Evan Scannapieco , Robert J. Thacker

We consider the degree to which "21 cm tomography" of the high-redshift Universe can distinguish different ionization histories. Using a new analytic model for the size distribution of HII regions that associates these ionized bubbles with…

Astrophysics · Physics 2009-09-29 Steven Furlanetto , Matias Zaldarriaga , Lars Hernquist
‹ Prev 1 8 9 10 Next ›