Search Publications
The evolution of the galaxy UV luminosity function at redshifts z ≃ 8 - 15 from deep JWST and ground-based near-infrared imaging
Moneti, A.; Bowler, R. A. A.; Cullen, F. +11 more
We reduce and analyse the available JWST ERO and ERS NIRCam imaging (SMACS0723, GLASS, CEERS) in combination with the latest deep ground-based near-infrared imaging in the COSMOS field (provided by UltraVISTA DR5) to produce a new measurement of the evolving galaxy UV luminosity function (LF) over the redshift range z = 8 - 15. This yields a new e…
Discovery and properties of ultra-high redshift galaxies (9 < z < 12) in the JWST ERO SMACS 0723 Field
Verma, A.; Conselice, C. J.; Adams, N. J. +8 more
We present a reduction and analysis of the 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 Reionization. We conduct this search by modelling photometric redshifts in several ways for all sources and by applying conserva…
The chemical enrichment in the early Universe as probed by JWST via direct metallicity measurements at z ∼ 8
Chevallard, Jacopo; Maseda, Michael V.; Carniani, Stefano +30 more
We analyse the chemical properties of three z~ 8 galaxies behind the galaxy cluster SMACS J0723.3-7327, observed as part of the Early Release Observations programme of the James Webb Space Telescope. Exploiting [O III]λ4363 auroral line detections in NIRSpec spectra, we robustly apply the direct Te method for the very first time at such…
Revealing galaxy candidates out to z 16 with JWST observations of the lensing cluster SMACS0723
Charlot, Stéphane; Chevallard, Jacopo; Mahler, Guillaume +8 more
One of the main goals of the JWST is to study the first galaxies in the Universe. We present a systematic photometric analysis of very distant galaxies in the first JWST deep field towards the massive lensing cluster SMACS0723. As a result, we report the discovery of two galaxy candidates at z ~ 16, only 250 million years after the big bang. We al…
A JWST/NIRCam study of key contributors to reionization: the star-forming and ionizing properties of UV-faint z 7-8 galaxies
Charlot, Stéphane; Chisholm, John; Chen, Zuyi +5 more
Spitzer/Infrared Array Camera (IRAC) imaging has revealed that the brightest z ~ 7-8 galaxies often exhibit young ages and strong nebular line emission, hinting at high ionizing efficiency among early galaxies. However, IRAC's limited sensitivity has long hindered efforts to study the fainter, more numerous population often thought largely respons…
The brightest galaxies at cosmic dawn
Treu, Tommaso; Trenti, Michele; Mason, Charlotte A.
Recent JWST observations suggest an excess of z ≳ 10 galaxy candidates above most theoretical models. Here, we explore how the interplay between halo formation time-scales, star formation efficiency, and dust attenuation affects the properties and number densities of galaxies observed in the early Universe. To guide intuition, we calculate the the…
The JWST FRESCO survey: legacy NIRCam/grism spectroscopy and imaging in the two GOODS fields
Chisholm, J.; Wuyts, S.; Schaerer, D. +38 more
We present the JWST cycle 1 53.8 h medium program FRESCO, short for 'First Reionization Epoch Spectroscopically Complete Observations'. FRESCO covers 62 arcmin2 in each of the two GOODS/CANDELS fields for a total area of 124 arcmin2 exploiting JWST's powerful new grism spectroscopic capabilities at near-infrared wavelengths. …
JWST/NIRSpec spectroscopy of z = 7-9 star-forming galaxies with CEERS: new insight into bright Lyα emitters in ionized bubbles
Charlot, Stéphane; Chen, Zuyi; Tang, Mengtao +9 more
We describe new JWST/NIRSpec observations of galaxies at z ≳ 7 taken from the CEERS survey. Previous observations of this area have revealed associations of Lyα emitters at redshifts (z = 7.5, 7.7, and 8.7) where the intergalactic medium (IGM) is thought to be mostly neutral, leading to suggestions that these systems are situated in large ionized …
Evolution of the UV LF from z 15 to z 8 using new JWST NIRCam medium-band observations over the HUDF/XDF
van Dokkum, Pieter G.; Illingworth, Garth D.; Brammer, Gabriel +7 more
We present the first constraints on the prevalence of z > 10 galaxies in the Hubble Ultra Deep Field (HUDF) leveraging new NIRCam observations from JEMS (JWST Extragalactic Medium-band Survey). These NIRCam observations probe redward of 1.6 µm, beyond the wavelength limit of HST, allowing us to search for galaxies to z > 10. These obse…
A surprising abundance of massive quiescent galaxies at 3 < z < 5 in the first data from JWST CEERS
Cullen, F.; McLure, R. J.; Dunlop, J. S. +9 more
We report a robust sample of 10 massive quiescent galaxies at redshift, z > 3, selected using the first data from the JWST Cosmic Evolution Early Release Science programme. Three of these galaxies are at 4 < z < 5, constituting the best evidence to date for quiescent galaxies significantly before z = 4. These extreme galaxies have stellar…