English
Related papers

Related papers: Ionization fronts and their interaction with densi…

200 papers

We use the SPHINX suite of high-resolution cosmological radiation hydrodynamics simulations to study how spatially and temporally inhomogeneous reionization impacts the baryonic content of dwarf galaxies and cosmic filaments. The SPHINX…

Modelling galaxy formation in hydrodynamic simulations has increasingly adopted various radiative transfer methods to account for photoionization feedback from young massive stars. However, the evolution of HII regions around stars begins…

Astrophysics of Galaxies · Physics 2023-11-06 Yunwei Deng , Hui Li , Rahul Kannan , Aaron Smith , Mark Vogelsberger , Greg L. Bryan

We show the universe was reionized twice, first at z~15-16 and second at z~6. Such an outcome appears inevitable, when normalizing to two well determined observational measurements, namely, the epoch of the final cosmological reionization…

Astrophysics · Physics 2009-06-15 Renyue Cen

The size distribution of ionized regions during the epoch of reionization -- a key ingredient in understanding the HI power spectrum observable by 21cm experiments -- can be modelled analytically using the excursion set formalism of random…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Aseem Paranjape , T. Roy Choudhury

The annihilation of dark matter particles releases energy, ionizing some of the gas in the Universe. We investigate the effect of dark matter halos on reionization. We show that the effect depends on the assumed density profile, the…

Astrophysics · Physics 2014-11-18 Aravind Natarajan , Dominik J. Schwarz

We examine the temperature structure of the IGM due to the passage of individual ionisation fronts using a radiative transfer (RT) code coupled to a particle-mesh (PM) N-body code. Multiple simulations were performed with different spectra…

Astrophysics · Physics 2009-11-11 Eric R. Tittley , Avery Meiksin

The prospect of detecting the first galaxies by observing their impact on the intergalactic medium as they reionized it during the first billion years leads us to ask whether such indirect observations are capable of diagnosing which types…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Ilian T. Iliev , Garrelt Mellema , Paul R. Shapiro , Ue-Li Pen , Yi Mao , Jun Koda , Kyungjin Ahn

We study the effects of the ionizing and dissociating photons produced by Pop III objects on the surrounding intergalactic medium. We find that the typical size of a H_2 photodissociated region is smaller than the mean distance between…

Astrophysics · Physics 2007-05-23 Benedetta Ciardi , Andrea Ferrara

One of the key observables of the reionization era is the distribution of neutral and ionized gas. Recently, Furlanetto, Zaldarriaga, & Hernquist developed a simple analytic model to describe the growth of HII regions during this era. Here,…

Astrophysics · Physics 2009-11-13 Steven R. Furlanetto , Matthew McQuinn , Lars Hernquist

We study the spatial fluctuations in the hydrogen ionizing background in the epoch following reionization (z ~ 5--6). The rapid decrease with redshift in the photon mean free path (m.f.p.), combined with the clustering of increasingly rare…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Andrei Mesinger , Steven Furlanetto

In a semi-numerical model of reionization, the evolution of ionization fraction is simulated approximately by the ionizing photon to baryon ratio criterion. In this paper we incorporate a semi-analytical model of galaxy formation based on…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Jie Zhou , Qi Guo , Gaochao Liu , Bin Yue , Yidong Xu , Xuelei Chen

We use a set of AMR hydrodynamic simulations post-processed with the radiative-transfer code RADAMESH to study how inhomogeneous HeII reionization affects the intergalactic medium (IGM). We propagate radiation from active galactic nuclei…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Michele Compostella , Sebastiano Cantalupo , Cristiano Porciani

We use a suite of cosmological hydrodynamic simulations including a self-consistent treatment for inhomogeneous reionisation to study the impact of galactic outflows and photoionisation heating on the volume-averaged recombination rate of…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-17 K. Finlator , S. Peng Oh , F. Özel , R. Davé

Cosmic reionization is thought to be primarily fueled by the first generations of galaxies. We examine their stellar and gaseous properties, focusing on the star formation rates and the escape of ionizing photons, as a function of halo…

Astrophysics of Galaxies · Physics 2016-12-14 Hao Xu , John H. Wise , Michael L. Norman , Kyungjin Ahn , Brian W. O'Shea

The morphology of the total gas and the neutral hydrogen (H I) distributions during the cosmological epoch of reionization can be quantified with Minkowski Functionals (MFs) of isodensity surfaces. We compute the MFs from the output of a…

Astrophysics · Physics 2008-11-26 Liron Gleser , Adi Nusser , Benedetta Ciardi , Vincent Desjacques

The role of feedback from massive stars is believed to be a key element in the evolution of molecular clouds. We use high-resolution 3D SPH simulations to explore the dynamical effects of a single O7 star located at the centre of a…

Astrophysics of Galaxies · Physics 2015-06-05 S. Walch , A. P. Whitworth , T. Bisbas , R. Wunsch , D. Hubber

Observations of high-redshift Ly-alpha sources are a major tool for studying the high-redshift Universe. We discuss the effect of the reionizing intergalactic medium on the observability of Ly-alpha sources based on large simulations of…

Astrophysics · Physics 2009-11-13 Ilian T. Iliev , Paul R. Shapiro , Patrick McDonald , Garrelt Mellema , Ue-Li Pen

Patchy cosmic reionization resulted in the ionizing UV background asynchronous rise across the Universe. The latter might have left imprints visible in present day observations. Several numerical simulation-based studies show correlations…

We show that the gaseous halos of collapsed objects introduce a substantial cumulative opacity to ionizing radiation, even after the smoothly distributed hydrogen in the intergalactic medium has been fully reionized. This opacity causes a…

Astrophysics · Physics 2009-11-07 Rennan Barkana , Abraham Loeb

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