Related papers: The First Galaxies: Signatures of the Initial Star…

We present a new determination of the evolving galaxy UV luminosity function (LF) over the extreme redshift range $12.5<z<18.5$, based on a wide-area search of $>$0.6 deg$^2$ of JWST NIRCam imaging containing $>150$ independent sight-lines.…

Massive, starbursting galaxies in the early Universe represent some of the most extreme objects in the study of galaxy evolution. One such source is HFLS3 (z~6.34), which was originally identified as an extreme starburst galaxy with mild…

The NASA/ESA/CSA James Webb Space Telescope (JWST) will be the successor to the Hubble Space Telescope and may be launched as early as mid-2011. The key scientific goals for JWST are discovering and understanding the formation of the first…

Recent results indicate the stellar initial mass function is not a strong function of star-forming environment or ``initial conditions'' (e.g. Meyer et al. 2000). Some studies suggest that a universal IMF may extend to sub-stellar masses…

JWST has measured an unprecedented abundance of galaxies above $z\gtrsim 4-5$, whose formation and evolution are still difficult to reconcile within traditional galaxy evolution models in a $\Lambda$CDM framework. Here, we present a study…

The first stars in the history of the Universe are likely to form in the dense central regions of 10^5-10^6 Msolar cold dark matter halos at z=10-50. The annihilation of dark matter particles in these environments may lead to the formation…

During the first 500 million years of cosmic history, the first stars and galaxies formed, seeding the Universe with heavy elements and eventually reionizing the intergalactic medium. Observations with JWST have uncovered a surprisingly…

The theory for the formation of the first population of stars (Pop III) predicts an initial mass function (IMF) dominated by high-mass stars, in contrast to the present-day IMF, which tends to yield mostly stars with masses less than 1…

The James Webb Space Telescope (JWST) is set to transform many areas of astronomy, one of the most exciting is the expansion of the redshift frontier to $z>10$. In its first year alone JWST should discover hundreds of galaxies, dwarfing the…

We use 30 high-resolution dark matter halos of the $Caterpillar$ simulation suite to probe the first stars and galaxies of Milky Way-mass systems. We quantify the environment of the high-$z$ progenitors of the Milky Way and connect them to…

We present optical and near-IR imaging and spectroscopy of SGAS J105039.6$+$001730, a strongly lensed galaxy at z $=$ 3.6252 magnified by $>$30$\times$, and derive its physical properties. We measure a stellar mass of…

Recent observations have successfully detected [O III] $88.3\,{\rm \mu m}$ and [C II] $157.6\,{\rm \mu m}$ lines from galaxies in the early Universe with the Atacama Large Millimeter Array (ALMA). Combining cosmological hydrodynamic…

Massive Pop III stars can die as energetic supernovae that enrich the early universe with metals and determine the properties of the first galaxies. With masses of about $10^9$ Msun at $z \gtrsim 10$, these galaxies are believed to be the…

We explore the stellar initial mass function (IMF) of a sample of 49 massive quiescent galaxies (MQGs) at 0.9$<$z$<$1.5. We base our analysis on intermediate resolution spectro-photometric data in the GOODS-N field taken in the…

The measured star-formation rates (SFRs) of galaxies comprise an important constraint on galaxy evolution and also on their cosmological boundary conditions. Any available tracer of the SFR depends on the shape of the mass-distribution of…

Recent JWST observations suggest an excess of $z\gtrsim10$ galaxy candidates above most theoretical models. Here, we explore how the interplay between halo formation timescales, star formation efficiency and dust attenuation affects the…

We present a new near-field cosmological probe of the initial mass function (IMF) of the first stars. Specifically, we constrain the lower-mass limit of the Population III (Pop III) IMF with the total number of stars in large, unbiased…

Observations with JWST have revealed an unexpected high abundance of bright z>10 galaxy candidates. We explore whether a stellar initial mass function (IMF) that becomes increasingly top-heavy towards higher redshifts and lower gas-phase…

We present deep spectroscopy with the Keck telescope of eight galaxies in the luminous X-ray cluster MS1054-03 at z=0.83. The data are combined with imaging observations from the Hubble Space Telescope (HST). The spectroscopic data are used…

JWST has revealed a population of super-luminous early galaxies with a volume density in excess of most expectations. The spectra reveal diverse properties: while some reveal strong emission lines characteristic of galaxies in the midst of…