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arXiv · 2602.01549

Stellar Mass Growth in the First Galaxies: Theory and Observation

Alan Dressler·Andrew Benson
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Abstract

We compare the growth in stellar mass of galaxies in the $6 2\times10^8 \mathrm{M}_\odot$ in the epoch $8<z<6$ had less than $M_*<\times10^8 \mathrm{M}_\odot$ prior to $z = 8$. Here too we find agreement between models and data, namely that these ~100 Myr 'bursts' had strong in situ growth at $z\le8$, or showed (in Galacticus) substantial stellar and/or gas-rich mergers, and 30-40 Myr 'starbursts' as are common in $z<3$ galaxies. We note that, if a theoretical simulation is unable to pass the test of matching the growth of stellar mass, any success in reproducing the luminosity function is meaningless.

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Alan Dressler, Andrew Benson. 2026-02-02. Stellar Mass Growth in the First Galaxies: Theory and Observation. https://arxiv.org/abs/2602.01549

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