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arXiv · 2508.08577

RUBIES spectroscopically confirms the high number density of quiescent galaxies from $\mathbf{2<z<5}$

Yunchong Zhang·Anna de Graaff·David J. Setton·Sedona H. Price·Rachel Bezanson·Claudia del P. Lagos·Sam E. Cutler·Ian McConachie·Nikko J. Cleri·Olivia R. Cooper·Rashmi Gottumukkala·Jenny E. Greene·Michaela Hirschmann·Gourav Khullar·Ivo Labbe·Joel Leja·Michael V. Maseda·Jorryt Matthee·Tim B. Miller·Themiya Nanayakkara·Katherine A. Suess·Bingjie Wang·Katherine E. Whitaker·Christina C. Williams
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Abstract

We present the number density of massive ($ \mathrm{ log (M_{*}/M_{\odot}) > 10.3} $) quiescent galaxies at $2 3$, most simulations fail to produce enough massive quiescent galaxies, suggesting the treatment of feedback and/or the channels for early efficient formation are incomplete in most galaxy evolution models.

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Yunchong Zhang, Anna de Graaff, David J. Setton, Sedona H. Price, Rachel Bezanson, Claudia del P. Lagos, Sam E. Cutler, Ian McConachie, Nikko J. Cleri, Olivia R. Cooper, Rashmi Gottumukkala, Jenny E. Greene, Michaela Hirschmann, Gourav Khullar, Ivo Labbe, Joel Leja, Michael V. Maseda, Jorryt Matthee, Tim B. Miller, Themiya Nanayakkara, Katherine A. Suess, Bingjie Wang, Katherine E. Whitaker, Christina C. Williams. 2025-08-12. RUBIES spectroscopically confirms the high number density of quiescent galaxies from $\mathbf{2<z<5}$. https://doi.org/10.3847/1538-4357%2Fae24e1

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