Search Publications

Confirmation and refutation of very luminous galaxies in the early Universe
DOI: 10.1038/s41586-023-06521-7 Bibcode: 2023Natur.622..707A

Papovich, Casey; Finkelstein, Steven L.; Buat, Véronique +34 more

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 medium1-3. Observations with the James Webb Space Telescope (JWST) have uncovered a surprisingly high abundance of candidates for early star-forming galaxies, wit…

2023 Nature
JWST 199
A JWST/NIRCam study of key contributors to reionization: the star-forming and ionizing properties of UV-faint z 7-8 galaxies
DOI: 10.1093/mnras/stad1919 Bibcode: 2023MNRAS.524.2312E

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…

2023 Monthly Notices of the Royal Astronomical Society
eHST JWST 199
Early Release Science of the exoplanet WASP-39b with JWST NIRSpec PRISM
DOI: 10.1038/s41586-022-05677-y Bibcode: 2023Natur.614..659R

Zhang, X.; Heng, K.; May, E. M. +91 more

Transmission spectroscopy1-3 of exoplanets has revealed signatures of water vapour, aerosols and alkali metals in a few dozen exoplanet atmospheres4,5. However, these previous inferences with the Hubble and Spitzer Space Telescopes were hindered by the observations' relatively narrow wavelength range and spectral resolving po…

2023 Nature
Gaia eHST JWST 199
An Ice Age JWST inventory of dense molecular cloud ices
DOI: 10.1038/s41550-022-01875-w Bibcode: 2023NatAs...7..431M

Egami, E.; McGuire, Brett A.; Sun, Fengwu +39 more

Icy grain mantles are the main reservoir of the volatile elements that link chemical processes in dark, interstellar clouds with the formation of planets and the composition of their atmospheres. The initial ice composition is set in the cold, dense parts of molecular clouds, before the onset of star formation. With the exquisite sensitivity of th…

2023 Nature Astronomy
JWST 196
The DESI Bright Galaxy Survey: Final Target Selection, Design, and Validation
DOI: 10.3847/1538-3881/accff8 Bibcode: 2023AJ....165..253H

Myers, Adam D.; Bailey, Stephen; Palanque-Delabrouille, Nathalie +57 more

Over the next 5 yr, the Dark Energy Spectroscopic Instrument (DESI) will use 10 spectrographs with 5000 fibers on the 4 m Mayall Telescope at Kitt Peak National Observatory to conduct the first Stage IV dark energy galaxy survey. At z < 0.6, the DESI Bright Galaxy Survey (BGS) will produce the most detailed map of the universe during the dark-e…

2023 The Astronomical Journal
Gaia 192
Gaia Data Release 3. Analysis of RVS spectra using the General Stellar Parametriser from spectroscopy
DOI: 10.1051/0004-6361/202243750 Bibcode: 2023A&A...674A..29R

Hatzidimitriou, D.; Schultheis, M.; Marshall, D. J. +77 more

Context. The chemo-physical parametrisation of stellar spectra is essential for understanding the nature and evolution of stars and of Galactic stellar populations. A worldwide observational effort from the ground has provided, in one century, an extremely heterogeneous collection of chemical abundances for about two million stars in total, with f…

2023 Astronomy and Astrophysics
Gaia 192
The brightest galaxies at cosmic dawn
DOI: 10.1093/mnras/stad035 Bibcode: 2023MNRAS.521..497M

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…

2023 Monthly Notices of the Royal Astronomical Society
JWST 186
Demographics of Young Stars and their Protoplanetary Disks: Lessons Learned on Disk Evolution and its Connection to Planet Formation
DOI: 10.48550/arXiv.2203.09930 Bibcode: 2023ASPC..534..539M

Lodato, G.; Williams, J. P.; Ansdell, M. +4 more

Since Protostars and Planets VI (PPVI), our knowledge of the global properties of protoplanetary and debris disks, as well as of young stars, has dramatically improved. At the time of PPVI, mm-observations and optical to near-infrared spectroscopic surveys were largely limited to the Taurus star-forming region, especially of its most massive disk …

2023 Protostars and Planets VII
Gaia 182
Early Release Science of the exoplanet WASP-39b with JWST NIRSpec G395H
DOI: 10.1038/s41586-022-05591-3 Bibcode: 2023Natur.614..664A

Carter, Aarynn L.; Gibson, Neale P.; Mikal-Evans, Thomas +89 more

Measuring the abundances of carbon and oxygen in exoplanet atmospheres is considered a crucial avenue for unlocking the formation and evolution of exoplanetary systems1,2. Access to the chemical inventory of an exoplanet requires high-precision observations, often inferred from individual molecular detections with low-resolution space-b…

2023 Nature
JWST 182
The JWST FRESCO survey: legacy NIRCam/grism spectroscopy and imaging in the two GOODS fields
DOI: 10.1093/mnras/stad2411 Bibcode: 2023MNRAS.525.2864O

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. …

2023 Monthly Notices of the Royal Astronomical Society
JWST 180