Related papers: Experimental Constraints on Self-consistent Reioni…
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.…
Context: Population III (Pop III) stars may be fast rotating. An expected consequence of fast rotation is strong internal mixing that deeply affects their evolutionary tracks in the Hertzsprung-Russell diagram and hence their ionising…
We study the evolution of the ionization state of the IGM at the end of the reionization epoch using spectra of a sample of nineteen quasars at 5.74<z<6.42 discovered in the SDSS. Three methods are used to trace IGM properties: (a) the…
I use cosmological simulations that incorporate a physically motivated approximation to three-dimensional radiative transfer that recovers correct asymptotic ionization front propagation speeds for some cosmologically relevant density…
We utilize GIZMO, coupled with newly developed sub-grid models for Population~III (Pop~III) and Population~II (Pop~II), to study the legacy of star formation in the pre-reionization Universe. We find that the Pop~II star formation rate…
Understanding when and how reionization happened is crucial for studying the early structure formation and the properties of first galaxies in the Universe. At $z>5.5$, the observed IGM optical depth shows a significant scatter, indicating…
We derive constraints on the thermal and ionization states of the intergalactic medium (IGM) at redshift $\approx$ 9.1 using new upper limits on the 21-cm power spectrum measured by the LOFAR radio-telescope and a prior on the ionized…
We study the impact of inhomogeneous hydrogen reionization on the thermal evolution of the intergalactic medium (IGM) using hydrodynamic + radiative transfer simulations where reionization is completed either early (z ~ 9) or late (z ~ 6).…
The first, self-consistent calculations are presented of the cosmological, H2-dissociating UV background produced during the epoch of reionization by the sources of reionization. Large-scale radiative transfer simulations of reionization…
The critical star formation rate density required to keep the intergalactic hydrogen ionised depends crucially on the average rate of recombinations in the intergalactic medium (IGM). This rate is proportional to the clumping factor C =…
In this paper we use a number of observations to construct an integrated picture of the ionisation in the interiors of quiescent warm opaque interstellar clouds and in the intercloud medium (ICM) outside dense HII regions and hot dilute…
Reionization is thought to have occurred in the redshift range of $6 < z < 9$, which is now being probed by both deep galaxy surveys and CMB observations. Using halo abundance matching over the redshift range $5<z<8$ and assuming smooth,…
Understanding the detailed process of cosmic reionization is one of the remaining problems in astrophysics and cosmology. Here we construct a model of cosmic reionization that includes contribution from high-$z$ galaxies and active galactic…
We present constraints on both the kinetic temperature of the intergalactic medium (IGM) at z=8.4, and on models for heating the IGM at high-redshift with X-ray emission from the first collapsed objects. These constraints are derived using…
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…
Recent observations have constrained the galaxy UV luminosity function up to z~10. However, these observations alone allow for a wide range of reionization scenarios due to uncertainties in the abundance of faint galaxies and the escape…
We use numerical simulations of hydrogen reionization by stellar sources in the context of LCDM cosmogonies to investigate the 21 (1+z) cm radio signal expected from the diffuse intergalactic medium (IGM) prior to the epoch of reionization…
Hydrodynamical simulations of galaxy formation such as the Illustris simulations have progressed to a state where they approximately reproduce the observed stellar mass function from high to low redshift. This in principle allows…
We revisit the question of the ionization of the diffuse medium in late type galaxies, by studying NGC 891. The most important challenge for the models considered so far was the observed increase of [OIII]/Hb, [OII]/Hb, and [NII]/Ha with…
Cross-correlations between 21cm observations and galaxy surveys provide a powerful probe of reionization by reducing foreground sensitivity while linking ionization morphology to galaxies. We quantify the constraining power of 21cm-Galaxy…