Related papers: A Lyman-{\alpha} protocluster at redshift 6.9
We investigate the physical properties and redshift evolution of simulated galaxies residing in protoclusters at cosmic noon, to understand the influence of the environment on galaxy formation. This work is to build clear expectations for…
To demonstrate the feasibility of studying the epoch of massive galaxy cluster formation in a more systematic manner using current and future galaxy surveys, we report the discovery of a large sample of proto-cluster candidates in the 1.62…
Protoclusters, galaxy clusters' high redshift progenitors, hold the keys to understanding the formation and evolution of clusters and their member galaxies. However, their cosmological distances and spatial extensions (tens of Mpc) have…
The case is made that the intracluster medium (ICM) in spiral-rich galaxy groups today probably has undergone much slower evolution than that in elliptical-rich groups and clusters. The environments of proto-clusters and proto-groups at z >…
In the early Universe finding massive galaxies that have stopped forming stars present an observational challenge as their rest-frame ultraviolet emission is negligible and they can only be reliably identified by extremely deep…
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…
The quest to discover the most distant galaxies has developed rapidly in the last decade. We are now exploring redshifts of 6 and beyond, when the Universe was less than a billion years old, an epoch when the previously-neutral…
We report the discovery of a very bright (m_R = 22.2) Lyman break galaxy at z = 3.03 that appears to be a massive system in a late stage of merging. Deep imaging reveals multiple peaks in the brightness profile with angular separations of…
The $\Lambda$CDM cosmological model successfully reproduces many aspects of the galaxy and structure formation of the universe. However, the growth of large-scale structures (LSSs) in the early universe is not well tested yet with…
The high ionization level and universal metallicity (1% solar) of the intergalactic gas at redshifts z<5 implies that nonlinear structure had started to form in the universe at earlier times than we currently probe. In Cold Dark Matter…
We present six spectroscopically confirmed massive protostructures, spanning a redshift range of $2.5<z<4.5$ in the Extended Chandra Deep Field South (ECDFS) field discovered as part of the Charting Cluster Construction in VUDS and ORELSE…
We have discovered six galaxies with spectroscopically confirmed redshifts of 4.8<z<5.8 in a single 44 square arcminute field imaged deeply in R, I and z-bands. All the spectra show an emission-line in the region around 7000-8400 angstroms…
Cosmological simulations are crucial tools in studying the Universe, but they typically do not directly match real observed structures. Constrained cosmological simulations, on the other hand, are designed to match the observed distribution…
Galaxies at very high redshift (z~3 or greater) are now accessible to wholesale observation, making possible for the first time a robust statistical assessment of their spatial distribution at lookback times approaching ~90% of the age of…
The epoch of reionization (6 < z < 10) marks the period in our universe when the first large galaxies grew to fruition, and began to affect the universe around them. Massive stars, and potentially accreting supermassive black holes, filled…
We determine the abundance of i'-band drop-outs in the HST/ACS GOODS surveys and the Hubble Ultra Deep Field (UDF). The majority of these sources are likely to be z~6 galaxies whose flux decrement arises from Lyman-alpha absorption. We have…
We report the discovery of a galaxy proto-cluster candidate (dubbed MACS0416-OD-z8p5) at a spectroscopic redshift of $z\sim8.47$, dating back to $\sim550$Myr after the Big Bang. The observations are part of the JWST Cycle-3 treasury…
The 8m class telescopes in the ground-based optical astronomy together with help from the ultra-sharp eye of the Hubble Space Telescope have enabled us to observe forming galaxies beyond redshift $z=5$. In particular, more than twenty…
We present results from the first robust investigation of galaxy morphology as a function of environment at z>1.5. Our study is motivated by the fact that star-forming galaxies contained within a protocluster at z=2.3 in the HS1700+64 field…
Radio Active Galactic Nuclei (RAGNs) are mainly found in dense structures (i.e., clusters/groups) at redshifts of z$<$2 and are commonly used to detect protoclusters at higher redshift. Here, we attempt to study the host and environmental…