English
Related papers

Related papers: The effect of minihaloes on cosmic reionization

200 papers

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…

Motivated by the recent detection by WMAP of a large optical depth to Thomson scattering -- implying a very early reionization epoch -- we assess a scenario where the universe was reionized by `miniquasars' powered by intermediate-mass…

Astrophysics · Physics 2008-11-26 Piero Madau , Martin J. Rees , Marta Volonteri , Francesco Haardt , S. Peng Oh

We present a new semi-analytical model of the population of satellite galaxies of the Milky Way, aimed at estimating the effect of the spatial structure of reionisation at galaxy scale on the properties of the satellites. In this model…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-08 Pierre Ocvirk , Dominique Aubert

We explore scenarios for reionizing the intergalactic medium with low galaxy ionizing photon escape fractions. We combine simulation-based halo-mass dependent escape fractions with an extrapolation of the observed galaxy rest-ultraviolet…

Galactic stellar halos have long been considered to contain fossil information on early dynamical and chemical evolution of galaxies. We propose that the surface brightness distributions of old stellar halos contain the influence of…

Astrophysics · Physics 2009-11-11 Kenji Bekki , Masashi Chiba

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 revisit constraints on small-scale primordial power from annihilation signals from dark matter minihalos. Using gamma rays and neutrinos from extragalactic minihalos and assuming the delta-function primordial spectrum, we show the…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-07 Tomohiro Nakama , Teruaki Suyama , Kazunori Kohri , Nagisa Hiroshima

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…

In warm dark matter scenarios structure formation is suppressed on small scales with respect to the cold dark matter case, reducing the number of low-mass halos and the fraction of ionized gas at high redshifts and thus, delaying…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-24 Laura Lopez-Honorez , Olga Mena , Sergio Palomares-Ruiz , Pablo Villanueva Domingo

Previously we identified a new class of early galaxy that we estimate contributes up to 30\% of the ionizing photons responsible for reionization. These are low mass halos in the range $M_h =10^{6.5}-10^{8} M_{\odot}$ that have been…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-07 Michael L Norman , Pengfei Chen , John H Wise , Hao Xu

Baryons both increase halo concentration through adiabatic contraction and expel mass through feedback processes. However, it is not well understood how the radiation fields prevalent during the epoch of reionization affect the evolution of…

Astrophysics of Galaxies · Physics 2023-01-18 Hanjue Zhu , Nickolay Y. Gnedin

Compared with the cold dark matter (CDM) model, in the warm dark matter (WDM) model formation of small scale structure is suppressed. It is often thought that this would delay the reionization of the intergalactic medium (IGM), as the star…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Bin Yue , Xuelei Chen

Recent observations of z~6 quasars and the cosmic microwave background imply a complex history to cosmic reionization. Such a history requires some form of feedback to extend reionization over a long time interval, but the nature of the…

Astrophysics · Physics 2009-11-10 Steven Furlanetto , Abraham Loeb

Early photoionization of the intergalactic medium is discussed in a nearly model-independent way, in order to investigate whether early structures corresponding to rare Gaussian peaks in a CDM model can photoionize the intergalactic medium…

Astrophysics · Physics 2009-10-07 Max Tegmark , Joseph Silk , Alain Blanchard

Cosmic reionization was driven by the imbalance between early sources and sinks of ionizing radiation, both of which were dominated by small-scale structure and are thus usually treated in cosmological reionization simulations by subgrid…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-05 Yi Mao , Jun Koda , Paul R. Shapiro , Ilian T. Iliev , Garrelt Mellema , Hyunbae Park , Kyungjin Ahn , Michele Bianco

A large population of Intermediate Mass Black Holes (IMBHs) might be produced at early cosmic times as a left over of the evolution of the very massive first stars. Accretion onto IMBHs provides a source of (re)ionizing radiation. We show…

Astrophysics · Physics 2009-11-13 R. Salvaterra , F. Haardt , A. Ferrara

We examine the reionization history of present-day galaxies by explicitly tracing the building blocks of halos from the Cosmic Reionization On Computers project. We track dark matter particles that belong to $z=0$ halos to trace the neutral…

Cosmology and Nongalactic Astrophysics · Physics 2019-12-02 Hanjue Zhu , Camille Avestruz , Nickolay Y. Gnedin

The reionization history of the intergalactic medium (IGM) at high redshift (z > 6) was likely strongly shaped by several global feedback processes. Because the earliest ionizing sources formed at the locations of the rare density peaks,…

Astrophysics · Physics 2008-11-26 Roban Hultman Kramer , Zoltan Haiman , S. Peng Oh

We estimate the maximum contribution to reionization from the first generation of massive stars, with zero metallicity, under the assumption that one of these stars forms with a fixed mass in every collapsed halo in which metal-free gas is…

Astrophysics · Physics 2007-05-23 Jose M. Rozas , Jordi Miralda-Escude , Eduard Salvador-Sole

We present self-consistent radiation hydrodynamic simulations of hydrogen reionization performed with Arepo-RT complemented by a state-of-the-art galaxy formation model. We examine how photoheating feedback, due to reionization, shapes the…

Astrophysics of Galaxies · Physics 2019-06-25 Xiaohan Wu , Rahul Kannan , Federico Marinacci , Mark Vogelsberger , Lars Hernquist