Talk detail

Participant	Arca Sedda, Manuel
Institution	University of Rome Tor Vergata - Via O. Raimondo - Rome - Italy - Italy

Session	DM4	Accepted		Order	Time
Talk	Oral abstract	Title	The possible formation of a nuclear star clusters in the galaxy Henize 2-10
Coauthors
Abstract	The central region of the galaxy Henize 2-10 (Kobulnicky et al. 1995; Johnson et al. 2000) hosts a black hole (BH) candidate with a mass Log (M_{BH} /M⊙ ) = 6.3 ± 1.1 (Reines et al. 2011). While this putative black hole does not appear to coincide with any central stellar over density, it is surrounded by 11 young massive clusters with masses above 10^5 M⊙ . The availability of high quality data on the structure of the galaxy and the age and mass of the clusters provides excellent initial conditions for studying the dynamical evolution of Henize 2-10s nucleus. Here we present a set of N -body simulations in which we model the future evolution of the central clusters and black hole to understand whether and how they will merge to form a nuclear star cluster. Nuclear star clusters (NSCs) are present in a majority of galaxies with stellar mass similar to Henize 2-10. While the results depend on the choice of initial conditions, we find that a NSC with mass MNSC ≃ 4 − 6 × 10^6 M⊙ and effective radius rNSC ≃ 2.6 − 4.1 pc will form within 0.2 Gyr. This work is the first showing, in a realistic realization of the host galaxy and its star cluster system, that the formation of a bright nucleus is a process that can happen after the formation of a central massive BH leading to a composite NSC+BH central system. The cluster merging process does not significantly affect the kinematics of the BH; its position changes by 1 pc and its velocity by < 2 km s^{−1} .
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