Related papers: The Highest-Redshift Balmer Breaks as a Test of $\…
We use very deep near-infrared photometry of the Hubble Deep Field South taken with ISAAC/VLT to identify a population of high redshift galaxies with rest- frame optical colors similar to those of nearby galaxies. The galaxies are chosen by…
We use a sample of 17 strong gravitational lens systems from the BELLS GALLERY survey to quantify the amount of low-mass dark matter haloes within the lensing galaxies and along their lines of sight, and to constrain the properties of dark…
This article concerns the formation and structure of dark matter halos, including (1) their radial density profiles, (2) their abundance, and (3) their merger rates. The last topic may be relevant to the nature of the small, bright,…
We explore the lowest mass limit that can be placed on the halo mass function in CDM using 28 strong gravitational lenses. For this purpose, we study an extreme model in which the halo mass function and mass-concentration relation follow…
We report the first detection of the dark matter distribution around Lyman break galaxies (LBGs) at high redshift through the Cosmic Microwave Background (CMB) lensing measurements with the public {\it Planck} PR3 $\kappa$ map. The LBG…
We search for galaxies with a strong Balmer break (Balmer Break Galaxies; BBGs) at $z \sim 6$ over a 0.41 deg$^2$ effective area in the COSMOS field. Based on rich imaging data, including data obtained with the Atacama Large…
Using a combination of N-body simulations with different resolutions, we study in detail how the concentrations of cold dark matter (CDM) halos depend on halo mass at different redshifts. We confirm that halo concentrations at the present…
We present a reduction and analysis of the \textit{James Webb Space Telescope} (JWST) SMACS~0723 field using new post-launch calibrations to conduct a search for ultra-high-redshift galaxies ($z > 9$) present within the Epoch of…
We derive an analytic model for the redshift evolution of linear-bias, allowing for interactions and merging of the mass-tracers, by solving a second order differential equation based on linear perturbation theory and the Friedmann-Lemaitre…
Recent data from the James Webb Space Telescope allow a first glimpse of galaxies at $z \gtrsim 11$. The most successful tool for identifying ultra-high-redshift candidates and inferring their properties is photometric template fitting.…
Recent studies at high redshift have revealed an enigmatic class of Little Red Dots (LRDs) with extreme Balmer breaks, stronger than in any stellar atmosphere. However, it is unclear whether such objects exist at lower redshift, especially…
Structures in Warm Dark Matter (WDM) models are exponentially suppressed below a certain scale, characterized by the dark matter particle mass, $m_{\rm x}$. Since structures form hierarchically, the presence of collapsed objects at…
We study the evolution of the mass function of dark matter halos in the concordance LCDM model at high redshift. We employ overlapping (multiple-realization) numerical simulations to cover a wide range of halo masses,…
We present the results of clustering analyses of Lyman break galaxies (LBGs) at $z\sim3$, $4$, and $5$ using the final data release of the Canada--France--Hawaii Telescope Legacy Survey (CFHTLS). Deep- and wide-field images of the CFHTLS…
Warm Dark Matter (WDM) particles with masses ($\sim$ kilo electronvolt) offer an attractive solution to the small-scale issues faced by the Cold Dark Matter (CDM) paradigm. The delay of structure formation in WDM models and the associated…
To understand the formation and evolution of galaxies at redshifts z < 10, one must invariably introduce specific models (e.g., for the star formation) in order to fully interpret the data. Unfortunately, this tends to render the analysis…
We analyse various low-redshift cosmological data from Type-Ia Supernova, Baryon Acoustic Oscillations, Time-Delay measurements using Strong-Lensing, $H(z)$ measurements using Cosmic Chronometers and growth measurements from large scale…
We present a semi-analytical model of star formation which explains simultaneously the observed UV luminosity function of high redshift Lyman break galaxies (LBGs) and luminosity functions of Lyman-alpha emitters. We consider both models…
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,…
The most luminous galaxies at high-redshift are generally considered to be hosted in massive dark-matter halos of comparable number density, hence residing at the center of overdensities/protoclusters. We assess the validity of this…