相关论文: The Neutral Islands during the Late Epoch of Reion…
The epoch of reionization (EoR) marks the last phase transition of hydrogen in our Universe, as it evolves from cold and neutral to hot and ionized in the intergalactic medium (IGM). While its endpoint and duration can be estimated from…
A key physical quantity during reionization is the size of HII regions. Previous studies found a characteristic bubble size which increases rapidly during reionization, with apparent agreement between simulations and analytic excursion set…
We present an improved matched filter method for detecting large ionized regions in 21 cm observations of the Epoch of Reionization. In addition to detection, the method constrains the properties of these regions, offering insights into the…
The bubble size distribution is a summary statistics that can be computed from the observed 21-cm signal from the Epoch of Reionization. As it depends only on the ionization field and is not limited to gaussian information, it is an…
The reionization of intergalactic hydrogen has received intense theoretical scrutiny over the past two decades. Here, we approach the process formally as a percolation process and phase transition. Using semi-numeric simulations, we…
Early results from JWST suggest that epoch-of-reionization (EoR) galaxies produce copious ionizing photons, which, if they escape efficiently, could cause reionization to occur too early. We study this problem using \jwst\ imaging and prism…
Detecting and characterizing individual ionized bubbles during the Epoch of Reionization (EoR) using the redshifted HI 21-cm signal provides a direct probe of the early ionizing sources and the intergalactic medium. We develop and validate…
Fronts are regions of transition from one state to another in a medium. They are present in many areas of science and applied mathematics, and modelling them and their evolution is often an effective way of treating the underlying phenomena…
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…
Reionization is inhomogeneous for two reasons: the clumpiness of the intergalactic medium (IGM) and clustering of the discrete ionizing sources. While numerical simulations can in principle take both into account, they are at present…
Point island models (PIMs) are presented for the formation of supported nanoclusters (or islands) during deposition on flat crystalline substrates at lower submonolayer coverages. These models treat islands as occupying a single adsorption…
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…
Mass-loss and radiation feedback from evolving massive stars produce galactic-scale superwinds, sometimes surrounded by pressure-driven bubbles. Using the time-dependent stellar population typically seen in star-forming regions, we conduct…
The distribution of ionised hydrogen during the epoch of reionization (EoR) has a complex morphology. We propose to measure the three-dimensional topology of ionised regions using the Betti numbers. These quantify the topology using the…
We present an efficient method to generate large simulations of the Epoch of Reionization (EoR) without the need for a full 3-dimensional radiative transfer code. Large dark-matter-only simulations are post-processed to produce maps of the…
We extend our previous SPH parameter study of the effects of photoionization from O-stars on star-forming clouds to include initially unbound clouds. We generate a set of model clouds in the mass range $10^{4}-10^{6}$M$_{\odot}$ with…
During the epoch of reionization (EoR), the 21-cm signal allows direct observation of the neutral hydrogen (HI) in the intergalactic medium (IGM). In the post-reionization era, this signal instead probes HI in galaxies, which traces the…
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…
In the present communication we describe the Island-Mainland transition, occurring in a square lattice, when black squares are randomly dropped on a white background. Initially clusters of black squares are observed on the connected white…
Deposition/removal of metal atoms on the hex reconstructed (100) surface of Au, Pt and Ir should present intriguing aspects, since a new island implies hex -> square deconstruction of the substrate, and a new crater the square -> hex…