Search Publications

UNCOVER: JWST Spectroscopy of Three Cold Brown Dwarfs at Kiloparsec-scale Distances
DOI: 10.3847/1538-4357/ad206f Bibcode: 2024ApJ...962..177B

Nanayakkara, Themiya; van Dokkum, Pieter; Fujimoto, Seiji +19 more

We report JWST/NIRSpec spectra of three distant T-type brown dwarfs identified in the Ultradeep NIRSpec and NIRCam ObserVations before the Epoch of Reionization (UNCOVER) survey of the Abell 2744 lensing field. One source was previously reported as a candidate T dwarf on the basis of NIRCam photometry, while two sources were initially identified a…

2024 The Astrophysical Journal
eHST JWST 39
JWST and ALMA Multiple-line Study in and around a Galaxy at z = 8.496: Optical to Far-Infrared Line Ratios and the Onset of an Outflow Promoting Ionizing Photon Escape
DOI: 10.3847/1538-4357/ad235c Bibcode: 2024ApJ...964..146F

Ouchi, Masami; Koekemoer, Anton M.; Richard, Johan +33 more

We present Atacama Large Millimeter/submillimeter Array (ALMA) deep spectroscopy for a lensed galaxy at z spec = 8.496 with $\mathrm{log}({M}_{\mathrm{star}}/{M}_{\odot })\sim 7.8$ whose optical nebular lines and stellar continuum are detected by JWST/NIRSpec and NIRCam Early Release Observations in the field of SMACS J0723.3–7327. Our …

2024 The Astrophysical Journal
Gaia eHST JWST 39
Strong gravitational lensing's 'external shear' is not shear
DOI: 10.1093/mnras/stae1375 Bibcode: 2024MNRAS.531.3684E

Koekemoer, Anton M.; Mahler, Guillaume; Frye, Brenda L. +20 more

The distribution of mass in galaxy-scale strong gravitational lenses is often modelled as an elliptical power-law plus 'external shear', which notionally accounts for neighbouring galaxies and cosmic shear along our line of sight. A small amount of external shear could come from these sources, but we show that the vast majority does not. Except in…

2024 Monthly Notices of the Royal Astronomical Society
eHST 39
Overview and public data release of the augmented Auriga Project: cosmological simulations of dwarf and Milky Way-mass galaxies
DOI: 10.1093/mnras/stae1598 Bibcode: 2024MNRAS.532.1814G

Springel, Volker; Grand, Robert J. J.; Gómez, Facundo A. +4 more

We present an extended suite of the Auriga cosmological gravo-magnetohydrodynamical 'zoom-in' simulations of 40 Milky Way-mass haloes and 26 dwarf galaxy-mass haloes run with the moving-mesh code AREPO. Auriga adopts the Lambda cold dark matter cosmogony and includes a comprehensive galaxy formation physics model following the coupled cosmic evolu…

2024 Monthly Notices of the Royal Astronomical Society
Gaia 39
Stellar Half-mass Radii of 0.5 z < 2.3 Galaxies: Comparison with JWST/NIRCam Half-light Radii
DOI: 10.3847/1538-4357/ad02ee Bibcode: 2024ApJ...960...53V

Bell, Eric F.; Franx, Marijn; Muzzin, Adam +13 more

We use CEERS JWST/NIRCam imaging to measure rest-frame near-IR light profiles of 435 M > 1010 M galaxies in the redshift range of 0.5 < z < 2.3. We compare the resulting rest-frame 1.5-2 µm half-light radii (R NIR) with stellar half-mass radii ( ${R}_{{{M}}_{\star }}$ ) derived with mu…

2024 The Astrophysical Journal
eHST JWST 39
JWST reveals widespread AGN-driven neutral gas outflows in massive z 2 galaxies
DOI: 10.1093/mnras/stae327 Bibcode: 2024MNRAS.528.4976D

Conroy, Charlie; Johnson, Benjamin D.; Belli, Sirio +15 more

We use deep JWST/NIRSpec R ~ 1000 slit spectra of 113 galaxies at $1.7 < z < 3.5$, selected from the mass-complete Blue Jay survey, to investigate the prevalence and typical properties of neutral gas outflows at cosmic noon. We detect excess Na ID absorption (beyond the stellar contribution) in 46 per cent of massive galaxies (log M*

2024 Monthly Notices of the Royal Astronomical Society
eHST JWST 38
Brown Dwarf Candidates in the JADES and CEERS Extragalactic Surveys
DOI: 10.3847/1538-4357/ad20d1 Bibcode: 2024ApJ...964...66H

Johnson, Benjamin D.; Lyu, Jianwei; Eisenstein, Daniel J. +13 more

By combining the James Webb Space Telescope (JWST)/NIRCam JADES and CEERS extragalactic data sets, we have uncovered a sample of 21 T and Y brown dwarf candidates at best-fit distances between 0.1 and 4.2 kpc. These sources were selected by targeting the blue 1–2.5 µm colors and red 3–4.5 µm colors that arise from molecular absorption …

2024 The Astrophysical Journal
eHST JWST 38
A New Population of Mid-infrared-selected Tidal Disruption Events: Implications for Tidal Disruption Event Rates and Host Galaxy Properties
DOI: 10.3847/1538-4357/ad18bb Bibcode: 2024ApJ...961..211M

Meisner, Aaron M.; Simcoe, Robert A.; Eilers, Anna-Christina +14 more

Most tidal disruption events (TDEs) are currently found in time-domain optical and soft X-ray surveys, both of which are prone to significant obscuration. The infrared (IR), however, is a powerful probe of dust-enshrouded environments; hence, we recently performed a systematic search of NEOWISE mid-IR data for nearby, obscured TDEs within roughly …

2024 The Astrophysical Journal
XMM-Newton 38
ΛCDM not dead yet: massive high-z Balmer break galaxies are less common than previously reported
DOI: 10.1093/mnras/stae1084 Bibcode: 2024MNRAS.530.2935D

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

Early JWST observations that targeted so-called double-break sources (attributed to Lyman and Balmer breaks at z > 7), reported a previously unknown population of very massive, evolved high-redshift galaxies. This surprising discovery led to a flurry of attempts to explain these objects' unexpected existence including invoking alternatives to t…

2024 Monthly Notices of the Royal Astronomical Society
Gaia eHST JWST 38
On the Nature of Disks at High Redshift Seen by JWST/CEERS with Contrastive Learning and Cosmological Simulations
DOI: 10.3847/1538-4357/ad05bb Bibcode: 2024ApJ...961...51V

Papovich, Casey; Finkelstein, Steven L.; Pérez-González, Pablo G. +26 more

Visual inspections of the first optical rest-frame images from JWST have indicated a surprisingly high fraction of disk galaxies at high redshifts. Here, we alternatively apply self-supervised machine learning to explore the morphological diversity at z ≥ 3. Our proposed data-driven representation scheme of galaxy morphologies, calibrated on mock …

2024 The Astrophysical Journal
JWST 38