Search Publications

A Steep Decline in the Galaxy Space Density beyond Redshift 9 in the CANUCS UV Luminosity Function
DOI: 10.3847/1538-4357/ad35bc Bibcode: 2024ApJ...966...74W

Willott, Chris J.; Martis, Nicholas S.; Rihtaršič, Gregor +15 more

We present a new sample of 158 galaxies at redshift z > 7.5 selected from deep James Webb Space Telescope (JWST) NIRCam imaging of five widely separated sight lines in the CANUCS survey. Two-thirds of the pointings and 80% of the galaxies are covered by 12–14 NIRCam filters, including seven to nine medium bands, providing accurate photometric r…

2024 The Astrophysical Journal
eHST JWST 46
Rapid Chemical Enrichment by Intermittent Star Formation in GN-z11
DOI: 10.3847/2041-8213/ad1de1 Bibcode: 2024ApJ...962L...6K

Ferrara, Andrea; Kobayashi, Chiaki

We interpret the peculiar supersolar nitrogen abundance recently reported by the James Webb Space Telescope observations for GN-z11 (z = 10.6) using our state-of-the-art chemical evolution models. The observed CNO ratios can be successfully reproduced—independently of the adopted initial mass function, nucleosynthesis yields, and presence of super…

2024 The Astrophysical Journal
JWST 46
A Candidate Supermassive Black Hole in a Gravitationally Lensed Galaxy at Z ≈ 10
DOI: 10.3847/2041-8213/ad391f Bibcode: 2024ApJ...965L..21K

Azadi, Mojegan; Jones, Christine; Volonteri, Marta +8 more

While supermassive black holes (SMBHs) are widely observed in the nearby and distant Universe, their origin remains debated with two viable formation scenarios with light and heavy seeds. In the light seeding model, the seed of the first SMBHs form from the collapse of massive stars with masses of 10–100 M , while the heavy seeding mod…

2024 The Astrophysical Journal
JWST 46
GN-z11: The environment of an active galactic nucleus at z = 10.603. New insights into the most distant Lyα detection
DOI: 10.1051/0004-6361/202347187 Bibcode: 2024A&A...687A.283S

Charlot, Stéphane; Carniani, Stefano; Übler, Hannah +23 more

Recent observations with the James Webb Space Telescope (JWST) have further refined the spectroscopic redshift of GN-z11, one of the most distant galaxies identified with the Hubble Space Telescope, at z = 10.603. The presence of extremely dense gas (> 1010 cm−3), the detection of high-ionisation lines and of CII*1335 emis…

2024 Astronomy and Astrophysics
JWST 46
Bright z ∼ 9 Galaxies in Parallel: The Bright End of the Rest-frame UV Luminosity Function from HST Parallel Programs
DOI: 10.3847/1538-4357/ad09dc Bibcode: 2024ApJ...961..209B

Papovich, Casey; Finkelstein, Steven L.; Bagley, Micaela B. +7 more

The abundance of bright galaxies at z > 8 can provide key constraints on models of galaxy formation and evolution, as the predicted abundance varies greatly when different physical prescriptions for gas cooling and star formation are implemented. We present the results of a search for bright z ∼ 9–10 galaxies selected from pure parallel Hubble …

2024 The Astrophysical Journal
eHST 45
Efficient NIRCam Selection of Quiescent Galaxies at 3 < z < 6 in CEERS
DOI: 10.3847/1538-4357/ad4cea Bibcode: 2024ApJ...970...68L

Papovich, Casey; Finkelstein, Steven L.; Pérez-González, Pablo G. +31 more

Substantial populations of massive quiescent galaxies at z ≥ 3 challenge our understanding of rapid galaxy growth and quenching over short timescales. In order to piece together this evolutionary puzzle, more statistical samples of these objects are required. Established techniques for identifying massive quiescent galaxies are increasingly ineffi…

2024 The Astrophysical Journal
eHST JWST 45
Small-amplitude Red Giants Elucidate the Nature of the Tip of the Red Giant Branch as a Standard Candle
DOI: 10.3847/2041-8213/ad284d Bibcode: 2024ApJ...963L..43A

Anderson, Richard I.; Eyer, Laurent; Koblischke, Nolan W.

The tip of the red giant branch (TRGB) is an important standard candle for determining luminosity distances. Although several 105 small-amplitude red giant stars (SARGs) have been discovered, variability was previously considered irrelevant for the TRGB as a standard candle. Here, we show that all stars near the TRGB are SARGs that foll…

2024 The Astrophysical Journal
Gaia 45
There is no place like home - finding birth radii of stars in the Milky Way
DOI: 10.1093/mnras/stae2364 Bibcode: 2024MNRAS.535..392L

Steinmetz, Matthias; Buck, Tobias; Freeman, Ken C. +6 more

Stars move away from their birthplaces over time via a process known as radial migration, which blurs chemo-kinematic relations used for reconstructing the Milky Way (MW) formation history. To understand the true time evolution of the MW, one needs to take into account the effects of this process. We show that stellar birth radii can be derived di…

2024 Monthly Notices of the Royal Astronomical Society
Gaia 45
The Sonora Substellar Atmosphere Models. IV. Elf Owl: Atmospheric Mixing and Chemical Disequilibrium with Varying Metallicity and C/O Ratios
DOI: 10.3847/1538-4357/ad18c2 Bibcode: 2024ApJ...963...73M

Fortney, Jonathan J.; Batalha, Natasha E.; Marley, Mark S. +7 more

Disequilibrium chemistry due to vertical mixing in the atmospheres of many brown dwarfs and giant exoplanets is well established. Atmosphere models for these objects typically parameterize mixing with the highly uncertain K zz diffusion parameter. The role of mixing in altering the abundances of C-N-O-bearing molecules has mostly been…

2024 The Astrophysical Journal
AKARI 45
The 40 pc sample of white dwarfs from Gaia
DOI: 10.1093/mnras/stad3773 Bibcode: 2024MNRAS.527.8687O

Gänsicke, B. T.; Tremblay, P. -E.; Hollands, M. A. +14 more

We present a comprehensive overview of a volume-complete sample of white dwarfs located within 40 pc of the Sun, a significant proportion of which were detected in Gaia Data Release 3 (DR3). Our DR3 sample contains 1076 spectroscopically confirmed white dwarfs, with just five candidates within the volume remaining unconfirmed (> 99 per cent spe…

2024 Monthly Notices of the Royal Astronomical Society
Gaia 44