K. Hainline

Discovery of the Lyman-$\alpha$ Forest in a Star-Forming Galaxy at $z \approx 7.57$: Implications for the Timing and Topology of Cosmic Reionization

The escape of ionizing photons from galaxies during the Epoch of Reionization is often inferred indirectly because the intervening neutral hydrogen in the intergalactic medium (IGM) is expected to absorb all flux blueward of Lyman-$\alpha$ at these redshifts. However, in this work, we report the significant detection (...

Two Exciting High-redshift Galaxy Candidates Turn Out to Be Two Exciting Brown Dwarfs

From the onset of observations of JWST we have discovered unexpectedly luminous galaxies at redshifts z > 10 and as high as z = 14. With their discovery, the question immediately followed as to where their progenitors are, since such progenitors should be within reach of existing surveys. However, the discovery of seve...

Mergers lighting the early Universe: modest star-formation enhancement without evidence for AGN or Lyα triggering

Galaxy mergers and interactions are often invoked to explain enhanced star formation, black hole growth, and mass build-up of galaxies at later cosmic times, but their effect is poorly understood at high redshift (z > 2). We use JADES data to analyse a mass-complete sample of 1968 galaxies at z = 3 − 9 with log(M⋆/M⊙...

JADES data release 4 – Paper I . Sample selection, observing strategy and redshifts of the complete spectroscopic sample

A Gravitationally Lensed Low-Luminosity AGN From The Cosmic Noon

Strong gravitational lensing provides a unique tool of studying intrinsically faint high-redshift active galactic nuclei (AGN). In particular, low-luminosity AGN (LLAGN) can probe black-hole growth in low-mass galaxies that current X-ray surveys cannot otherwise access. We investigate the nature and physical properties...

Spatially Resolved Active Galactic Nucleus Ionization and Star Formation at Cosmic Noon with JWST/JEMS

At cosmic noon (z ≈ 2–3), both star formation and active galactic nucleus (AGN) activity peaked, each playing a significant role in ionizing interstellar gas on galaxy-wide scales. The spatial distribution of this ionized gas provides a direct probe of how AGN and stellar ionization influence the gaseous reservoirs of...

JADES: The Star Formation and Dust Reddening Properties of Galaxies at 3 < z < 7

We present the star formation and dust content properties for a sample of 646 galaxies at redshifts 3 < z < 7 as part of the JADES survey. Our analysis is based on measurements of the Hα/Hβ Balmer decrement using medium resolution (R ∼ 1000) spectroscopic observations with the JWST/NIRSpec microshutter assembly. Stella...

PhotoIFU: NIRCam as a Photometric Integral Field Unit for Mapping Feedback in Galaxies

We present PhotoIFU, a workflow that uses deep multi-band imaging as a low-resolution photometric integral field unit. Applied to PSF-matched JWST/NIRCam imaging, PhotoIFU treats each spatial pixel as a coarse SED element and fits the pixel SEDs with Prospector to map resolved stellar-population and ISM-related propert...