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arXiv · 2310.12895

Physical properties of circumnuclear ionising clusters. II. NGC 7469

S. Zamora·Ángeles I. Díaz
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Abstract

Circumnuclear star forming regions (CNSFR) are massive clusters found close to galactic nuclei. These entities give us an excellent opportunity to study star formation in environments with high metallicity and to relate it with active galactic nuclei. Our principal aim is to derive the physical properties and dynamical masses of the CNSFRs in the two rings of the spiral NGC 7469, categorized as a Luminous Infrared Galaxy (ULIRG) and hosting a Seyfert 1 nucleus. We have used archival data obtained with the MUSE spectrograph attached to one of the ESO VLT telescopes and we have applied the techniques shown in the first paper of the series. Regions in the studied galaxy show large sizes which can be explained by the stellar winds produced by WR stars. The inner ring regions seem to be more compact than the outer ones, showing higher electron densities and filling factors. The young stellar population of the clusters has contributions of ionising populations with ages around 5 Ma and its masses constitute less than a 1\% of the total mass of each cluster. The inner ring regions which are close to the active galactic nucleus probably are the only ones that have enough mass to survive the action of the AGN. They constitute the $\sim$ 90 \% of the total inner ring mass.

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S. Zamora, Ángeles I. Díaz. 2023-10-19. Physical properties of circumnuclear ionising clusters. II. NGC 7469. https://doi.org/10.1051/0004-6361/202346960

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