Constraining the formation of the large Nuclear Star Cluster of FCC47 with MUSE + AO (Katja Fahrion; European Southern Observatory, Garching)

From August 21, 2019 13:15 until August 21, 2019 13:45

At Instituto de Astrofísica, Pontificia Universidad Católica, Vicuña Mackenna 4860, Santiago, Chile

Categories: Seminarios

Nuclear star clusters (NSCs) are found in at least 70% of all galaxies; however, despite their abundance it is still debated how they form. The currently discussed scenarios propose that NSCs could either form from infalling gas directly at the galactic center or through the accretion of globular clusters (GCs) that spiral inwards due to dynamical friction, but also a composite scenario is possible. In the GC accretion scenario, the NSC would reflect the low angular momentum and low metallicities of the surrounding GC population, whereas the in-situ scenario would lead to a higher angular momentum and higher metallicities from subsequent star bursts.

Constraining NSC formation in galaxies therefore requires a complete view of both the kinematics and chemical properties of the host galaxy, the NSC and the GC system. To achieve this task, we use IFU data from the MUSE instrument of the early-type galaxy FCC47, which has a remarkably large NSC (Reff ~ 66 pc) and a very rich GC system.

In addition to an analysis of the galaxy light kinematics and stellar population properties, we extract optical spectra of the GCs to determine radial velocities and metallicities. In combination with a dynamical model, our panoramic view of the galaxy and its star clusters allows to put constraints on the formation of FCC47’s massive NSC.