The DAWN JWST Archive: A spectroscopically-informed population study of the physical properties of galaxies at z>2

Rashmi Gottumukkala; Gabriel Brammer; Sune Toft; Mengyuan Xiao; Anna de Graaff; Pascal A. Oesch; Francesco Valentino; Katherine E. Whitaker; William M. Baker; Laia Barrufet; Rachel Bezanson; Leindert A. Boogaard; Alex J. Cameron; Olivia R. Cooper; Emma Giovinazzo; Kasper E. Heintz; Michaela Hirschmann; Kei Ito; Ivo Labbe; Minju M. Lee; Zach J. Lewis; Jorryt Matthee; Ian McConachie; Desika Narayanan; Clara L. Pollock; Sedona H. Price; David J. Setton; Marko Shuntov; Pieter van Dokkum; Bingjie Wang; Joris Witstok; Yunchong Zhang; Pengpei Zhu

arXiv · 2610.15901

The DAWN JWST Archive: A spectroscopically-informed population study of the physical properties of galaxies at z>2

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Abstract

Charting the evolution of star-formation, stellar mass and dust build-up over cosmic time relies on the accurate characterisation of the stellar population properties of high redshift galaxies. We present a catalogue of spectroscopically derived physical properties for ~12,000 galaxies at z>2, with archival JWST/NIRSpec PRISM spectroscopy and JWST/NIRCam imaging from the DAWN JWST Archive. We present a custom version of the SED fitting code BAGPIPES, used to perform joint spectrophotometric modelling of PRISM spectra and broadband NIRCam photometry. In doing so, we publicly release a science-ready catalogue of the physical properties of galaxies beyond cosmic noon. We report key physical properties, such as stellar masses, star-formation rates (SFR) and timescales, and V-band dust attenuation (Av). We further probe the recent star-formation histories (SFH) of galaxies via their SFRs on 3 Myr, 10 Myr, and 100 Myr timescales, capturing both rising and falling recent SFHs. Through dust-corrected ugi colour-colour diagrams of massive galaxies, we show how quiescent and dusty galaxies populate this colour space at z>2, with galaxies experiencing a recent downturn in star-formation occupying distinct parameter space. We also study the dustiest galaxies in our sample, showing that they are preferentially more massive and strongly star-forming relative to the parent sample, residing on the high-mass end of the star-forming main-sequence. The slope of the attenuation curve has a strong dependence on Av, varying from steep to shallow as the dust attenuation increases and the specific star-formation rate decreases. Our findings show that the unparalleled number statistics of this catalogue of spectroscopically derived stellar population properties uniquely enables the study star-formation, quenching and dust properties of galaxies from cosmic noon to cosmic dawn.

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Rashmi Gottumukkala, Gabriel Brammer, Sune Toft, Mengyuan Xiao, Anna de Graaff, Pascal A. Oesch, Francesco Valentino, Katherine E. Whitaker, William M. Baker, Laia Barrufet, Rachel Bezanson, Leindert A. Boogaard, Alex J. Cameron, Olivia R. Cooper, Emma Giovinazzo, Kasper E. Heintz, Michaela Hirschmann, Kei Ito, Ivo Labbe, Minju M. Lee, Zach J. Lewis, Jorryt Matthee, Ian McConachie, Desika Narayanan, Clara L. Pollock, Sedona H. Price, David J. Setton, Marko Shuntov, Pieter van Dokkum, Bingjie Wang, Joris Witstok, Yunchong Zhang, Pengpei Zhu. 2026-10-11. The DAWN JWST Archive: A spectroscopically-informed population study of the physical properties of galaxies at z>2. https://arxiv.org/abs/2610.15901

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