Related papers: Galaxies at High Redshift and Reionization
We determine the space density of UV-luminous star-burst galaxies at z~6 using deep HST ACS SDSS-i' (F775W) and SDSS-z' (F850LP) and VLT ISAAC J and K_s band imaging of the Chandra Deep Field South. We find 8 galaxies and one star with…
We provide a review of our current knowledge of galaxies throughout the first billion years of cosmic history. This field has undergone a transformation in the last two years following the launch of $\textit{JWST}$, and we aim to deliver an…
(Abridged) This work explores the existence of high redshift massive galaxies unveiled with Spitzer+IRAC, but missed by conventional selection techniques based on optical and near-infrared observations. To this end, we use the…
In this contribution we briefly describe our recent results on the properties of Lyman break galaxies at z~5 obtained from deep and wide blank field surveys using Subaru telescope, and through the comparison with samples at lower redshift…
The redshift-dependent fraction of color-selected galaxies revealing Lyman alpha emission has become the most valuable constraint on the evolving neutrality of the early intergalactic medium. However, in addition to resonant scattering by…
The fraction of ionizing photons escaping from galaxies, $f_{esc}$, is at the same time a crucial parameter in modelling reionization and a very poorly known quantity, especially at high redshift. Recent observations are starting to…
We have obtained spectroscopic redshifts using the Keck-I telescope for a sample of 73 submillimeter (submm) galaxies for which precise positions are available. The galaxies lie at redshifts out to z=3.6, with a median redshift of 2.2. The…
Galaxies had their most significant impact on the Universe when they assembled their first generations of stars. Energetic photons emitted by young, massive stars in primeval galaxies ionized the intergalactic medium surrounding their host…
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 unique high-resolution wide-field imaging capabilities of HST with ACS have allowed the characterization of galaxies at redshift 6, less than 1 Gyr from recombination. The dropout technique, applied to deep ACS i, z images in the RCDS…
It is thought that the first generations of massive stars in the Universe were an important, and quite possibly dominant, source of the ultra-violet radiation that reionized the hydrogen gas in the intergalactic medium (IGM); a state in…
Deep spectroscopic observations of z~6.5 galaxies have revealed a marked decline with increasing redshift in the detectability of Lyman-alpha emission. While this may offer valuable insight into the end of the reionisation process, it…
(Abridged) We review recent observations that suggest the star formation rate density is declining over 3$<z<$7 and illustrate the challenges that this poses in explaining the assembled stellar mass in z$\sim$6 galaxies deduced from Spitzer…
We present new results from our search for z~7 galaxies from deep spectroscopic observations of candidate z-dropouts in the CANDELS fields. Despite the extremely low flux limits achieved by our sensitive observations, only 2 galaxies have…
JWST has recently sparked a new era of Ly$\alpha$ spectroscopy, delivering the first measurements of the Ly$\alpha$ escape fraction and velocity profile in typical galaxies at $z\simeq6-10$. These observations offer new prospects for…
The dwarf galaxies of the Local Group are believed to be similar to the most abundant galaxies during the epoch of reionization (z>6). As a result of their proximity, there is a wealth of information that can be obtained about these…
We report the discovery of a Lyman-alpha-emitting galaxy at redshift z=6.545 serendipitously identified in the course of spectroscopic follow-up of hard X-ray sources on behalf of the Serendipitous Extragalactic X-Ray Source Identification…
JWST observations of high redshift galaxies are used to measure their star formation histories - the buildup of stellar mass in the earliest galaxies. Here we use a novel analysis program, SEDz*, to compare near-IR spectral energy…
The fraction of Lyman-$\alpha$ emitters among the galaxy population has been found to increase from $z\sim0$ to $z\sim6$ and drop dramatically at $z>6$. This drop has been interpreted as an effect of an increasingly neutral intergalactic…
We discuss new constraints on the epoch of cosmic reionization and test the assumption that most of the ionizing photons responsible arose from high redshift star-forming galaxies. Good progress has been made in charting the end of…