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arXiv · 2609.27048

In-Situ Star Formation in a Thick Disk: A Model for Metal Enrichment of Mrk 573

Hannalore J. Gerling-Dunsmore·Mitchell C. Begelman·Jared A. Goldberg·Taeho Ryu·Dominika Ł. Król
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Abstract

Recent observations of the nearby Seyfert galaxy Mrk 573 found that the galactic nucleus and bicone regions surrounding the jet are significantly metal-enriched. In this paper, we develop a simple model for the observed metal enrichment, assuming a population of stars in the $10 - 30 \, M_{\odot}$ range formed in-situ in the accretion disk. We assume the stars form according to a Salpeter initial mass function and generate the typical metal yields expected of field stars of the same mass. We find that in the thick disk ($H/r \sim 0.1$) case, a Salpeter population of stars can easily explain the observed metal enrichment and provide limits on the formation model; we also argue that a thin disk ($H/r \lesssim 0.01$) is incompatible with the observed metal enrichment. In our model, AGN metallicity scales most strongly with disk thickness, implying a potentially powerful observable diagnostic.

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Hannalore J. Gerling-Dunsmore, Mitchell C. Begelman, Jared A. Goldberg, Taeho Ryu, Dominika Ł. Król. 2026-09-22. In-Situ Star Formation in a Thick Disk: A Model for Metal Enrichment of Mrk 573. https://arxiv.org/abs/2609.27048

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