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arXiv · 2406.11571

PRIMER: JWST/MIRI reveals the evolution of star-forming structures in galaxies at z<2.5

Yipeng Lyu·Benjamin Magnelli·David Elbaz·Pablo G. Pérez-González·Camila Correa·Emanuele Daddi·Carlos Gómez-Guijarro·James S. Dunlop·Norman A. Grogin·Anton M. Koekemoer·Derek J. McLeod·Shiying Lu
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Abstract

The stellar structures of star-forming galaxies (SFGs) undergo significant size growth during their mass assembly and must pass through a compaction phase as they evolve into quiescent galaxies (QGs). To shed light on the mechanisms behind this structural evolution, we study the morphology of the star-forming components of 665 SFGs at 0 10^{10.5}M_\odot$). The compact star-forming components of these galaxies are also concentrated and slightly spheroidal, suggesting that this compaction phase can build dense bulge in-situ. Finally, we identify a third population of SFGs (19%), with both compact stellar and star-forming components. The density of their stellar cores resemble those of QGs and are compatible with being the descendants of EC galaxy. Overall, the structural evolution of SFGs is mainly dominated by a secular inside-out growth, which can, however, be interrupted by violent compaction phase(s) that can build dominant stellar bulges like those in massive SFGs or QGs.

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Yipeng Lyu, Benjamin Magnelli, David Elbaz, Pablo G. Pérez-González, Camila Correa, Emanuele Daddi, Carlos Gómez-Guijarro, James S. Dunlop, Norman A. Grogin, Anton M. Koekemoer, Derek J. McLeod, Shiying Lu. 2024-06-17. PRIMER: JWST/MIRI reveals the evolution of star-forming structures in galaxies at z<2.5. https://doi.org/10.1051/0004-6361/202451067

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