F. Cullen

MEGATRON: The Physical Origins of Steep UV Slopes at High Redshift

Harley Katz, Nicholas Choustikov, Aayush Saxena +7

The ultraviolet (UV) spectral slope, $β$ , serves as a fundamental probe of stellar population properties and interstellar medium conditions in galaxies. At high redshift, a small s…

A clear detection of proper motion confirms that the claimed $z ≃ 32$ galaxy candidate, "Capotauro'', is a Y-type brown dwarf

F. -Y. F. Liu, D. J. McLeod, B. J. Sutlieff +13

The compact red source ``Capotauro'', discovered in deep JWST imaging in 2025, has been suggested as a possible galaxy candidate at redshift $z ≃ 32$ on account of its extreme N…

Unprecedented Constraints on Gas Flows at High Redshift Using Deep JWST/NIRSpec Observations from the LyC22, EXCELS, and AURORA Surveys

Emily Kehoe, Alice E. Shapley, Adam C. Carnall +25

We investigate how low-ionization gas flows in typical star-forming galaxies at $z \sim 3$ depend on galaxy intrinsic properties and viewing angle. For this analysis we use JWST/NIRS…

Galaxy clusters in the VIDEO fields: detection and characterisation in the context of MOONRISE

Pierre Galois, Christophe Benoist, Gianluca Castignani +21

We analyse the cluster content of the $\sim 4.5 deg^{2}$ XMM-LSS and CDFS VIDEO fields which are expected to be partially covered by the upcoming MOONRISE survey. Using AMI…

astro-ph.GA2026★ 1 cited

The JWST EXCELS survey: The ages and abundances of $3 < z < 5$ massive quiescent galaxies show that downsizing was already in place by $z ≃ 4$

Ho-Hin Leung, Adam C. Carnall, Elizabeth Taylor +21

We present deep, medium-resolution $λ = 1 - 5 μ$ m JWST/NIRSpec spectroscopy for 14 quiescent galaxies at $3 < z < 5$ with $lo g_{10} (M_{*} / M_{⊙}) > 10$ , obtained as part of t…

astro-ph.IM2026

Illuminating the Physics of Cosmic Origin and Evolution: A UK Space Frontiers 2035 White Paper

Florian Beutler, Eva-Maria Mueller, Seshadri Nadathur +61

Understanding the Universe's origins and evolution remains one of the most fundamental challenges in modern cosmology. This white paper explores three key science priorities in thi…

astro-ph.GA2026★ 2 cited

Spectroscopic confirmation of a large and luminous galaxy with weak emission lines at $z = 13.53$

Callum T. Donnan, Derek J. McLeod, Ross J. McLure +15

We present JWST/NIRSpec PRISM observations of a robust galaxy candidate at $z ≃ 14$ , selected from pure-parallel NIRCam imaging; PAN-z14-1. The NIRSpec spectrum allows confirmat…

The JWST EXCELS survey: Outflows in 1.5 < z < 5 quiescent and recently quenched galaxies are likely relics from episodic AGN activity

Elizabeth Taylor, Adam C. Carnall, David Maltby +24

We investigate the presence and origin of neutral gas outflows and inflows in 13 post-starburst (PSB) and quiescent galaxies at redshifts 1.8 $\leq$ z $\leq$ 4.6, using JWST NIRSpe…

The AURORA Survey: The Mass -- Metallicity and Fundamental Metallicity Relations at $z \sim 2.3$ Based Purely on Direct $T_{e}$ Metallicities

Ali Ahmad Khostovan, Ryan L. Sanders, Alice E. Shapley +14

We present new constraints on the Mass -- Metallicity (MZR) and Fundamental Metallicity Relations (FMR) using a sample of 34 galaxies at $1.38 \leq z \leq 3.5$ (median $z = 2.28$ ). The…

The AURORA Survey: Constraining Chemical Enrichment Pathways at Cosmic Noon with Argon Abundances

Jack Foley, Alice Shapley, Ryan Sanders +11

We present argon abundances from a sample of 46 star-forming galaxies at $z = 2 - 3.5$ from the Assembly of Ultradeep Rest-Optical Observations Revealing Astrophysics (AURORA) program.…

MEGA: Spectrophotometric SED Fitting of Little Red Dots Detected in JWST MIRI

Kaila Ronayne, Casey Papovich, Allison Kirkpatrick +13

We analyze eight spectroscopically confirmed Little Red Dots (LRDs) at redshifts $z = 5.1 - 8.7$ with JWST/NIRCam, NIRSpec, and MIRI data. The LRDs have red NIRCam colors, F150W-F444…

astro-ph.GA2025★ 2 cited

The JWST EXCELS survey: Insights into the nature of quenching at cosmic noon

Maya Skarbinski, Kate Rowlands, Katherine Alatalo +19

We study 24 massive quiescent galaxies with $lo g M_{*} / M_{⊙} > 10$ at $1 < z < 3$ with JWST/NIRSpec medium-resolution observations from the Early eXtragalactic C…

astro-ph.GA2025★ 4 cited

The AURORA Survey: High-Redshift Empirical Metallicity Calibrations from Electron Temperature Measurements at z=2-10

Ryan L. Sanders, Alice E. Shapley, Michael W. Topping +29

We present detections of auroral emission lines of [OIII], [OII], [SIII], and [SII] in deep JWST/NIRSpec spectroscopy for 41 star-forming galaxies at $z = 1.4 - 7.2$ from the AURORA su…

ChemZz I: Comparing Oxygen and Iron Abundance Patterns in the Milky Way, the Local Group and Cosmic Noon

Stephanie Monty, Allison L. Strom, Thomas M. Stanton +7

Our understanding of the chemical evolution of galaxies has advanced through measurements from both distant galaxies across redshift, and our own Milky Way (MW). To form a comprehe…

The AURORA Survey: Robust Helium Abundances at High Redshift Reveal A Subpopulation of Helium-Enhanced Galaxies in the Early Universe

Danielle A. Berg, Ryan L. Sanders, Alice E. Shapley +16

We present the first robust helium (He) abundance measurements in star-forming galaxies at redshifts $1.6 ≲ z ≲ 3.3$ using deep, moderate-resolution JWST/NIRSpec spectr…

CLASSY XII: Nitrogen Enrichment Shaped by Gas Density and Feedback

Karla Z. Arellano-Córdova, Danielle A. Berg, Matilde Mingozzi +25

We investigate the chemical evolution of N/O using a sample of 45 local star-forming galaxies (SFGs) from the CLASSY survey. This sample spans a wide range of galaxy properties, wi…

Very bright, very blue, and very red: JWST CAPERS analysis of highly luminous galaxies with extreme UV slopes at $z = 10$

Callum T. Donnan, Mark Dickinson, Anthony J. Taylor +37

We present JWST/NIRSpec PRISM observations of three luminous ( $M_{UV} < - 20$ ) galaxies at $z \sim 10$ observed with the CAPERS Cycle 3 program. These galaxies exhibit extreme UV sl…

CAPERS-LRD-z9: A Gas Enshrouded Little Red Dot Hosting a Broad-line AGN at z=9.288

Anthony J. Taylor, Vasily Kokorev, Dale D. Kocevski +49

We present CAPERS-LRD-z9, a little red dot (LRD) which we confirm to be a $z = 9.288$ broad-line AGN (BLAGN). First identified as a high-redshift LRD candidate from PRIMER NIRCam pho…

astro-ph.GA2025★ 5 cited

The JWST/AURORA Survey: Multiple Balmer and Paschen Emission Lines for Individual Star-forming Galaxies at z=1.5-4.4. I. A Diversity of Nebular Attenuation Curves and Evidence for Non-Unity Dust Covering Fractions

Naveen A. Reddy, Alice E. Shapley, Ryan L. Sanders +14

We present the nebular attenuation curves and dust covering fractions for 24 redshift z=1.5-4.4 star-forming galaxies using multiple Balmer and Paschen lines from the JWST/AURORA s…

The AURORA Survey: Tracing Galactic Outflows at $z ≳ 2.5$ with JWST/NIRSpec NUV Absorption Lines

Emily Kehoe, Alice E. Shapley, Ryan L. Sanders +13

We probe galactic-scale outflows in star-forming galaxies at $z ≳ 2.5$ drawn from the \textit{JWST}/NIRSpec AURORA program. For the first time, we directly compare outflow prop…

CAPERS Observations of Two UV-Bright Galaxies at z>10. More Evidence for Bursting Star Formation in the Early Universe

Vasily Kokorev, Óscar A. Chávez Ortiz, Anthony J. Taylor +38

We present the first results from the CAPERS survey, utilizing PRISM observations with the JWST/NIRSpec MSA in the PRIMER-UDS field. With just 14 % of the total planned data volume…

astro-ph.GA2025★ 7 cited

JWST PRIMER: A deep JWST study of all ALMA-detected galaxies in PRIMER COSMOS -- dust-obscured star-formation history back to z $≃$ 7

Feng-Yuan Liu, James S. Dunlop, Ross J. McLure +15

We use the deep NIRCam and MIRI imaging from the JWST PRIMER survey to study the properties of (sub)mm sources detected by ALMA in the centre of the COSMOS field, with the aim of b…