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arXiv · 2402.14084

Diverse Oxygen Abundance in Early Galaxies Unveiled by Auroral Line Analysis with JWST

Takahiro Morishita·Massimo Stiavelli·Claudio Grillo·Piero Rosati·Stefan Schuldt·Michele Trenti·Pietro Bergamini·Kristan N. Boyett·Ranga-Ram Chary·Nicha Leethochawalit·Guido Roberts-Borsani·Tommaso Treu·Eros Vanzella
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Abstract

We present deep JWST NIRSpec observations in the sightline of MACS J1149.5+2223, a massive cluster of galaxies at $z=0.54$. We report the spectroscopic redshift of 28 sources at $3 7$, i.e. comparable to the most metal poor galaxies in the local Universe. The search of primordial galaxies may be accomplished by extending toward a lower mass and/or by investigating inhomogeneities at smaller spatial scales. Lastly, we investigate potential systematics caused by the limitation of JWST's MSA observations. Caution is warranted when the target exceeds the slit size, as this situation could allow an overestimation of "global" metallicity, especially under the presence of strong negative metallicity gradient.

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Takahiro Morishita, Massimo Stiavelli, Claudio Grillo, Piero Rosati, Stefan Schuldt, Michele Trenti, Pietro Bergamini, Kristan N. Boyett, Ranga-Ram Chary, Nicha Leethochawalit, Guido Roberts-Borsani, Tommaso Treu, Eros Vanzella. 2024-02-21. Diverse Oxygen Abundance in Early Galaxies Unveiled by Auroral Line Analysis with JWST. https://arxiv.org/abs/2402.14084

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