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arXiv · 2401.06842

Two rest-frame wavelength measurements of galaxy sizes at $z<1$: the evolutionary effects of emerging bulges and quenched newcomers

Angelo George·Ivana Damjanov·Marcin Sawicki·Stéphane Arnouts·Guillaume Desprez·Stephen Gwyn·Vincent Picouet·Simon Birrer·John Silverman
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Abstract

We analyze the size evolution of $16000$ star-forming galaxies (SFGs) and $5000$ quiescent galaxies (QGs) with mass $M_*>10^{9.5}M_\odot$ at $0.1 9$ are red and only QGs have $\log{\Sigma}_1>9.7$. The size of $M_*=M_0$ QGs grows by $50\%$ ($110\%$) in the UV (visible) light. Up to $\sim20\%$ of this increase in size of massive QGs is due to newcomers (recently quenched galaxies). However, newcomers cannot explain the observed pace in the size growth of QGs; that trend has to be dominated by processes affecting individual galaxies, such as minor mergers and accretion.

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Angelo George, Ivana Damjanov, Marcin Sawicki, Stéphane Arnouts, Guillaume Desprez, Stephen Gwyn, Vincent Picouet, Simon Birrer, John Silverman. 2024-01-12. Two rest-frame wavelength measurements of galaxy sizes at $z<1$: the evolutionary effects of emerging bulges and quenched newcomers. https://arxiv.org/abs/2401.06842

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