相关论文: Taxing the Rich: Recombinations and Bubble Growth …
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…
By depleting the ionizing photon budget available to expand cosmic HII regions, recombining systems (or Lyman limit systems) can have a large impact during (and following) cosmic reionization. Unfortunately, directly resolving such…
One of the most dramatic signatures of the reionization era may be the enormous ionized bubbles around luminous quasars (with radii reaching ~40 comoving Mpc), which may survive as "fossil'' ionized regions long after their source shuts…
We discuss the role of recombinations in the IGM, and the related concept of the clumping factor, during cosmic reionization. The clumping factor is, in general, a local quantity that depends on the local over-density and the scale below…
The central overlap phase of cosmological hydrogen reionization is fundamentally a change in the topology of ionized regions. Before overlap, ionized bubbles grew in isolation. During overlap, they merge into a percolating ionized medium,…
Constraining when and how reionisation began is pivotal for understanding when the first galaxies formed. Lyman-alpha (Ly$\alpha$) emission from galaxies is currently our most promising probe of these early stages. At z>7 the majority of…
Using the largest cosmological reionization simulation to-date (~24 billion particles), we use the genus curve to quantify the topology of neutral hydrogen distribution on scales > 1 Mpc as it evolves during cosmological reionization. We…
The topology of cosmic reionization, the sizes, shapes, and connectivity of ionized bubbles is a primary observable of next-generation 21\,cm experiments. We show that this topology is sensitive to the microphysics of dark matter.…
Density inhomogeneity in the intergalactic medium (IGM) can boost the recombination rate of ionized gas substantially, affecting the growth of HII regions during reionization. Previous attempts to quantify this effect typically failed to…
The history of the transition from a neutral intergalactic medium (IGM) to one that is almost fully ionized can reveal the character of cosmological ionizing sources. We study the evolution of the volume filling factor of HII and HeIII…
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…
Reionization is an inhomogeneous process, thought to begin in small ionized bubbles of the intergalactic medium (IGM) around overdense regions of galaxies. Recent Lyman-alpha (Ly$\alpha$) studies during the epoch of reionization show…
The reionization of hydrogen in the intergalactic medium (IGM) is a crucial landmark in the history of the universe, but the processes through which it occurs remain mysterious. In particular, recent numerical and analytic work suggest that…
Searches for Lyman-alpha emission lines are among the most effective ways to identify high-redshift galaxies. They are particularly interesting because they probe not only the galaxies themselves but also the ionization state of the…
We use fully self-consistent numerical simulations of cosmic reionization, completed under the Cosmic Reionization On Computers (CROC) project, to explore how well the recombinations in the ionized IGM can be quantified by the effective…
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…
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…
While most of the inter-galactic medium (IGM) today is permeated by ionized hydrogen, it was largely filled with neutral hydrogen for the first 700 million years after the Big Bang. The process that ionized the IGM (cosmic reionization) is…
We present general properties of ionized hydrogen (HII) bubbles and their growth based on a state-of-the-art large-scale (100 Mpc/h) cosmological radiative transfer simulation. The simulation resolves all halos with atomic cooling at the…
We have studied the IGM reionization process in its full cosmological context including structure evolution and a realistic galaxy population. We have used a combination of high-resolution N-body simulations (to describe the dark matter and…