Search Publications

Dust in Little Red Dots
DOI: 10.3847/2041-8213/ad7ba7 Bibcode: 2024ApJ...975L...4C

Casey, Caitlin M.; Long, Arianna S.; McKinney, Jed +5 more

JWST has revealed a ubiquitous population of "little red dots" (LRDs) at z ≳ 4, selected via their red rest-frame optical emission and compact morphologies. They are thought to be reddened by dust, whether in tori of active galactic nuclei (AGNs) or the interstellar medium, though none have direct dust detections to date. Informed by the average c…

2024 The Astrophysical Journal
eHST JWST 15
Properties of the brightest young stellar clumps in extremely lensed galaxies at redshifts 4 to 5
DOI: 10.1093/mnras/stae565 Bibcode: 2024MNRAS.529.2162M

Richard, Johan; Adamo, Angela; Messa, Matteo +2 more

We study the populations of stellar clumps in three high-redshift galaxies, at z = 4.92, 4.88, and 4.03, gravitationally lensed by the foreground galaxy clusters MS1358, RCS0224, and MACS0940, respectively. The lensed galaxies consist of multiple counter-images with large magnifications, mostly above $\mu > 5$ and in some cases reaching $\mu &g…

2024 Monthly Notices of the Royal Astronomical Society
Gaia eHST 15
In This Day and Age: An Empirical Gyrochronology Relation for Partially and Fully Convective Single Field Stars
DOI: 10.3847/1538-3881/ad28b9 Bibcode: 2024AJ....167..159L

Angus, Ruth; Foreman-Mackey, Daniel; Lu, Yuxi(Lucy) +1 more

Gyrochronology, the field of age dating stars using mainly their rotation periods and masses, is ideal for inferring the ages of individual main-sequence stars. However, due to the lack of physical understanding of the complex magnetic fields in stars, gyrochronology relies heavily on empirical calibrations that require consistent and reliable ste…

2024 The Astronomical Journal
Gaia 15
JWST MIRI MRS Observations of T Cha: Discovery of a Spatially Resolved Disk Wind
DOI: 10.3847/1538-3881/ad22e1 Bibcode: 2024AJ....167..127B

Pascucci, Ilaria; Gorti, Uma; Xie, Chengyan +8 more

Understanding when and how circumstellar disks disperse is crucial to constrain planet formation and migration. Thermal winds powered by high-energy stellar photons have long been theorized to drive disk dispersal. However, evidence for these winds is currently based only on small (∼3–6 km s‑1) blueshifts in [Ne II] 12.81 µm lines…

2024 The Astronomical Journal
Gaia JWST 15
Deep Hubble Space Telescope Photometry of Large Magellanic Cloud and Milky Way Ultrafaint Dwarfs: A Careful Look into the Magnitude–Size Relation
DOI: 10.3847/1538-4357/ad393c Bibcode: 2024ApJ...967...72R

Choi, Yumi; van der Marel, Roeland P.; Torrey, Paul +16 more

We present deep Hubble Space Telescope photometry of 10 targets from Treasury Program GO-14734, including six confirmed ultrafaint dwarf (UFD) galaxies, three UFD candidates, and one likely globular cluster. Six of these targets are satellites of, or have interacted with, the Large Magellanic Cloud (LMC). We determine their structural parameters u…

2024 The Astrophysical Journal
Gaia eHST 15
The Size–Mass Relation at Rest-frame 1.5 µm from JWST/NIRCam in the COSMOS-WEB and PRIMER-COSMOS Fields
DOI: 10.3847/1538-4357/ad5c6a Bibcode: 2024ApJ...972..134M

Bell, Eric F.; Franx, Marijn; van der Wel, Arjen +4 more

We present the galaxy stellar mass–size relation in the rest-frame near-IR (1.5 µm) and its evolution with redshift up to z = 2.5. Sérsic profiles are measured for ∼26,000 galaxies with stellar masses M > 109 M from JWST/NIRCam F277W and F444W imaging provided by the COSMOS-WEB and PRIMER surveys using…

2024 The Astrophysical Journal
eHST JWST 15
TESS Cycle 2 observations of roAp stars with 2-min cadence data
DOI: 10.1093/mnras/stad3800 Bibcode: 2024MNRAS.527.9548H

Handler, G.; Derekas, A.; Niemczura, E. +47 more

We present the results of a systematic search of the Transiting Exoplanet Survey Satellite (TESS) 2-min cadence data for new rapidly oscillating Ap (roAp) stars observed during the Cycle 2 phase of its mission. We find seven new roAp stars previously unreported as such and present the analysis of a further 25 roAp stars that are already known. Thr…

2024 Monthly Notices of the Royal Astronomical Society
Gaia 15
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
Science with a Small Two-Band UV-Photometry Mission I: Mission Description and Follow-up Observations of Stellar Transients
DOI: 10.1007/s11214-024-01048-3 Bibcode: 2024SSRv..220...11W

Behar, E.; Chang, Hsiang-Kuang; Merc, J. +33 more

This is the first in a collection of three papers introducing the science with an ultra-violet (UV) space telescope on an approximately 130 kg small satellite with a moderately fast re-pointing capability and a real-time alert communication system approved for a Czech national space mission. The mission, called Quick Ultra-Violet Kilonova surveyor…

2024 Space Science Reviews
eHST 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