Related papers: Feedback from Galaxy Formation: Escaping Ionizing …
We model the escape of ionizing radiation from high-redshift galaxies using high-resolution Adaptive Mesh Refinement N-body + hydrodynamics simulations. Our simulations include time-dependent and spatially-resolved transfer of ionizing…
In this talk I discuss the role of proto-globular clusters as the dominant sources of radiation that reionised hydrogen in the intergalactic medium (IGM) at redshift z~6. Observations at lower redshifts indicate that only a small fraction,…
The part played by stars in the ionization of the intergalactic medium remains an open question. A key issue is the proportion of the stellar ionizing radiation that escapes the galaxies in which it is produced. Spectroscopy of gamma-ray…
The physical origin of low escape fractions of ionizing radiation derived from massive star-forming galaxies at $z\sim3$-$4$ is not well understood. We perform idealised disc galaxy simulations to understand how galactic properties such as…
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…
A fundamental requirement for reionizing the Universe is that a sufficient fraction of the ionizing photons emitted by galaxies successfully escapes into the intergalactic medium. However, due to the scarcity of high-redshift observational…
Investigating how small-scale physical processes shape large-scale astrophysical phenomena is one of the key science themes of the Astro2020 decadal Survey. An example of this interplay is Cosmic Reionization, where ionizing photons from…
There has been great progress in recent years in discovering star forming galaxies at high redshifts (z>5), close to the epoch of reionization of the intergalactic medium (IGM). The WFC3 and ACS cameras on the Hubble Space Telescope have…
We show that the cosmic star formation rate per comoving volume should exhibit a distinct drop around the reionization redshift, when the HII regions in the intergalactic medium around individual ionizing sources first overlapped. The drop…
Approximately 30% of all massive stars in the Galaxy are runaways with velocities exceeding 30 km/s. Their high speeds allow them to travel ~0.1-1 kpc away from their birth place before they explode at the end of their several Myr…
The fraction of ionizing photons (fesc) that escape from z>6 galaxies is an important parameter when assessing the role of these objects in the reionization of the Universe, but the opacity of the intergalactic medium precludes a direct…
We couple the DELPHI framework for galaxy formation with a model for the escape of ionizing photons to study both its variability with galaxy assembly and the resulting key reionization sources. In this model, leakage either occurs through…
Compact, low-mass galaxies with strong nebular emission are considered promising candidates for efficient ionizing photon production and escape. We present a spatially resolved analysis of 189 galaxies at redshifts $z \sim 6.7-7.6$ in JADES…
We present a first sample of 117 [OIII]$\lambda\lambda$4960,5008-selected star-forming galaxies at $5.33 < z < 6.93$ detected in JWST/NIRCam 3.5$\mu$m slitless spectroscopy of a $6.5 \times 3.4$ arcmin$^2$ field centered on the…
Combing the three-dimensional radiative transfer (RT) calculation and cosmological SPH simulations, we study the escape fraction of ionizing photons (f_esc) of high-redshift galaxies at z=3-6. Our simulations cover the halo mass range of…
A problem still unsolved in cosmology is the identification of the sources of radiation able to reionize HI in the intergalactic medium (IGM) by z~6. Theoretical works and observations seem to indicate that the fraction, f_esc, of HI…
We describe a new method for simulating ionizing radiation and supernova feedback in the analogues of low-redshift galactic disks. In this method, which we call star-forming molecular cloud (SFMC) particles, we use a ray-tracing technique…
The Lyman continuum (LyC) flux escaping from high-z galaxies into the IGM is a fundamental quantity to understand the physical processes involved in the reionization epoch. We have investigated a sample of star-forming galaxies at z~3.3 in…
The fraction of ionizing photons escaping from high-redshift star-forming galaxies remains a key obstacle in evaluating whether galaxies were the primary agents of cosmic reionization. We previously proposed using the covering fraction of…
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…