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arXiv · 1908.00774

Using MUSE-AO observations to constrain the formation of the large nuclear star cluster in FCC47

Katja Fahrion·Mariya Lyubenova·Glenn van de Ven·Michael Hilker
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Abstract

Nuclear star clusters (NSCs) are found in at least 70% of all galaxies, but their formation path is still unclear. In the most common scenarios, NSCs form in-situ from the galaxy's central gas reservoir, through merging of globular clusters (GCs), or through a combination of the two. As the scenarios pose different expectations for angular momentum and stellar population properties of the NSC in comparison to the host galaxy and the GC system, it is necessary to characterise the stellar light, NSC, and GCs simultaneously. Wide-field observations with modern integral field units such as the Multi Unit Spectroscopic Explorer (MUSE) allow to perform such studies. However, at large distances, NSCs usually are not resolved in MUSE observations. The particularly large NSC (R_eff $\sim$ 66 pc) of the early-type galaxy FCC47 at distance of $\sim$ 20 Mpc is an exception and is therefore an ideal laboratory to constrain NSC formation of external galaxies.

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Katja Fahrion, Mariya Lyubenova, Glenn van de Ven, Michael Hilker. 2019-08-02. Using MUSE-AO observations to constrain the formation of the large nuclear star cluster in FCC47. https://doi.org/10.1017/s1743921319006811

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