Search Publications

Physical properties of extreme emission-line galaxies at z ∼ 4–9 from the JWST CEERS survey
DOI: 10.1051/0004-6361/202449904 Bibcode: 2024A&A...691A..59L

Kartaltepe, J. S.; Dickinson, M.; Finkelstein, S. L. +22 more

Context. Extreme emission line galaxies (EELGs) are typically characterized by high equivalent widths (EWs) which are driven by elevated specific star formation rates (sSFRs) in low-mass galaxies with subsolar metallicities and little dust. Such extreme systems are exceedingly rare in the local universe, but the number density of EELGs increases w…

2024 Astronomy and Astrophysics
eHST JWST 15
Could very low-metallicity stars with rotation-dominated orbits have been driven by the bar?
DOI: 10.1051/0004-6361/202348593 Bibcode: 2024A&A...691L...1Y

Li, Chengdong; Sestito, Federico; Ibata, Rodrigo A. +12 more

The most metal-poor stars (e.g., [Fe/H] ≤ –2.5) are the ancient fossils from the early assembly epoch of our Galaxy. They very likely formed before the the thick disk. Recent studies have shown that a non-negligible fraction of them have prograde planar orbits, which means that their origin is a puzzle. It has been suggested that a later-formed ro…

2024 Astronomy and Astrophysics
Gaia 15
Probing the physics of star formation (ProPStar). I. First resolved maps of the electron fraction and cosmic-ray ionization rate in NGC 1333
DOI: 10.1051/0004-6361/202347997 Bibcode: 2024A&A...686A.162P

Caselli, Paola; Chen, Mike; Neri, Roberto +11 more

Context. Electron fraction and cosmic-ray ionization rates in star-forming regions are important quantities in astrochemical modeling and are critical to the degree of coupling between neutrals, ions, and electrons, which regulates the dynamics of the magnetic field. However, these are difficult quantities to estimate.
Aims: We aim to derive …

2024 Astronomy and Astrophysics
Herschel 14
BUFFALO/Flashlights: Constraints on the abundance of lensed supergiant stars in the Spock galaxy at redshift 1
DOI: 10.1051/0004-6361/202346761 Bibcode: 2024A&A...681A.124D

Koekemoer, Anton M.; Mahler, Guillaume; Richard, Johan +28 more

In this work, we present a constraint on the abundance of supergiant (SG) stars at redshift z ≈ 1, based on recent observations of a strongly lensed arc at this redshift. First we derived a free-form model of MACS J0416.1-2403 using data from the Beyond Ultra-deep Frontier Fields and Legacy Observations (BUFFALO) program. The new lens model is bas…

2024 Astronomy and Astrophysics
eHST 14
Asteroseismology of the young open cluster NGC 2516. I. Photometric and spectroscopic observations
DOI: 10.1051/0004-6361/202348901 Bibcode: 2024A&A...686A.142L

Li, Gang; Bedding, Timothy R.; Aerts, Conny +8 more

Context. Asteroseismic modelling of isolated stars presents significant challenges due to the difficulty in accurately determining stellar parameters, particularly the stellar age. These challenges can be overcome by observing stars in open clusters whose coeval members share an initial chemical composition. The light curves from the all-sky surve…

2024 Astronomy and Astrophysics
Gaia 14
A quasar-galaxy merger at z ∼ 6.2: Rapid host growth via the accretion of two massive satellite galaxies
DOI: 10.1051/0004-6361/202449239 Bibcode: 2024A&A...689A.219D

Strauss, Michael A.; Fan, Xiaohui; Trebitsch, Maxime +38 more

We present JWST/NIRSpec integral field spectroscopy in the rest-frame optical bands of the system PJ308–21, a quasar at z = 6.2342 caught as its host galaxy interacts with companion galaxies. We detect the spatially extended emission of several emission lines (Hα, Hβ, [O III], [N II], [S II], and He II), which we used to study the properties of th…

2024 Astronomy and Astrophysics
JWST 14
Spatially resolved emission lines in galaxies at 4 ≤ z < 10 from the JADES survey: Evidence for enhanced central star formation
DOI: 10.1051/0004-6361/202449980 Bibcode: 2024A&A...692A.184T

Charlot, Stéphane; Carniani, Stefano; Übler, Hannah +19 more

We present the first statistical investigation of spatially resolved emission-line properties in a sample of 63 low-mass galaxies at 4 ≤ z < 10 using James Webb Space Telescope (JWST)/NIRSpec Micro Shutter Assembly (MSA) data from the JWST Advanced Deep Extragalactic (JADES) survey, focusing on deep, spatially resolved spectroscopy in the GOODS…

2024 Astronomy and Astrophysics
JWST 14
GA-NIFS: JWST/NIRSpec IFS view of the z ∼ 3.5 galaxy GS5001 and its close environment at the core of a large-scale overdensity
DOI: 10.1051/0004-6361/202451021 Bibcode: 2024A&A...691A.153L

Pérez-González, Pablo G.; Charlot, Stéphane; Parlanti, Eleonora +19 more

We present JWST Near-Infrared Spectrograph (NIRSpec) observations in integral field spectroscopic (IFS) mode of the galaxy GS5001 at redshift z = 3.47, the central member of a candidate protocluster in the GOODS-S field. The data cover a field of view (FoV) of 4″ × 4″ (∼30 × 30 kpc2) and were obtained as part of the Galaxy Assembly with…

2024 Astronomy and Astrophysics
Gaia eHST JWST 14
Establishing a mass-loss rate relation for red supergiants in the Large Magellanic Cloud
DOI: 10.1051/0004-6361/202449383 Bibcode: 2024A&A...686A..88A

Zapartas, E.; Munoz-Sanchez, G.; de Wit, S. +3 more

Context. The high mass-loss rates of red supergiants (RSGs) drastically affect their evolution and final fate, but their mass-loss mechanism remains poorly understood. Various empirical prescriptions scaled with luminosity have been derived in the literature, yielding results with a dispersion of two to three orders of magnitude.
Aims: We det…

2024 Astronomy and Astrophysics
AKARI Gaia 14
Young, wild, and free: The early expansion of star clusters
DOI: 10.1051/0004-6361/202347420 Bibcode: 2024A&A...683A..10D

Dalessandro, E.; Vesperini, E.; Livernois, A. +1 more

Early expansion plays a fundamental role in the dynamical evolution of young star clusters. However, until very recently most of our understanding of cluster expansion was based only on indirect evidence or on statistically limited samples of clusters. Here we present a comprehensive kinematic analysis of virtually all known young Galactic cluster…

2024 Astronomy and Astrophysics
Gaia 14