Probing the stellar populations and star formation history of early-type galaxies at $0 < z < 1.1$ in the rest-frame ultraviolet

Sadman Ali; Roberto De Propris; Chul Chung; Steven Phillipps; Malcolm Bremer; Masato Onodera; Marcin Sawicki; Guillaume Desprez; Stephen Gwyn

arXiv · 2403.08301

Probing the stellar populations and star formation history of early-type galaxies at $0 < z < 1.1$ in the rest-frame ultraviolet

Sadman Ali·Roberto De Propris·Chul Chung·Steven Phillipps·Malcolm Bremer·Masato Onodera·Marcin Sawicki·Guillaume Desprez·Stephen Gwyn

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Abstract

We measure the evolution of the rest-frame $NUV-V$ colors for early-type galaxies in clusters at $0 3$. The blue UV colors of early-type galaxies at low-intermediate redshifts are likely driven by this sub-population being enriched in helium up to $\sim44\%$. At $z>0.8$ (when the extra UV component has not yet appeared) the data allows us to constrain the star formation histories of galaxies by fitting models to the evolution of their UV colors: we find that the epoch at which the stellar populations formed ranges between $3<z_{form}<10$ (corresponding to $0.5-2.2$ Gyrs after the Big Bang) with a star-formation e-folding timescale of $\tau=0.35-0.7$ Gyr, suggesting that these galaxies formed the majority of stars at very high redshift, with a brief yet intense burst of star-formation activity. The star formation history and chemical evolution of early-type galaxies resemble those of globular clusters, albeit on much larger scales.

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Sadman Ali, Roberto De Propris, Chul Chung, Steven Phillipps, Malcolm Bremer, Masato Onodera, Marcin Sawicki, Guillaume Desprez, Stephen Gwyn. 2024-03-13. Probing the stellar populations and star formation history of early-type galaxies at $0 < z < 1.1$ in the rest-frame ultraviolet. https://arxiv.org/abs/2403.08301

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