0587981 - ASÚ 2025 RIV GB eng J - Journal Article
Peißker, F. - Zajaček, M. - Labaj, M. - Thomkins, L. - Elbe, A. - Eckart, A. - Labadie, L. - Karas, Vladimír - Sabha, N. B. - Steiniger, L. - Melamed, M.
The evaporating massive embedded stellar cluster IRS 13 close to Sgr A*. II. kinematic structure.
Astrophysical Journal. Roč. 970, č. 1 (2024), č. článku 74. ISSN 0004-637X. E-ISSN 1538-4357
R&D Projects: GA ČR(CZ) GX21-06825X; GA MŠMT LM2023047
Institutional support: RVO:67985815
Keywords : supermassive black holes * galactic center * younger stellar object * young massive clusters * intermediate-mass black holes
OECD category: Astronomy (including astrophysics,space science)
Impact factor: 4.9, year: 2022
Method of publishing: Open access

The existence of two distinct and apparently unrelated populations of dusty stellar objects in the Nuclear Stellar Cluster of the Milky Way, namely IRS 13 and the S-cluster, are potentially prone to a general process describing the star formation history in the Galactic center (GC). The former cluster is thought to be entangled in the clockwise and counterclockwise disks, a large-scale stellar distribution revealed by the analysis of stars at different distances from Sgr A*, the supermassive black hole in the GC. Recently, this large-scale distribution was reported to exhibit a multidisk structure with at least four components. Motivated by this finding, we revisit the anisotropic IRS 13 cluster and find strong evidence for a disk-like structure. An examination of about 50 individual stellar orbits reveals a new structure that does not follow any trend known in the literature. Furthermore, we investigate the possibility of an inspiral cluster undergoing star formation processes, as proposed by several authors. Using a simplified N-body simulation to reproduce our observational results, we conclude that, under certain conditions, a massive cluster can migrate from the Circum Nuclear Disk toward the inner parsec. Based on this classification, we revisit the large-scale NACO Very Large Telescope (VLT) observations of IRS 13 and find evidence for a separation of the cluster into a gravitationally stable core remnant and a dissipating part. With the velocity-resolved H30 alpha line and the broadband spectral energy distribution of IRS 13 E3, we provide tentative support for the existence of an intermediate-mass black hole of similar to 3 x 104 M circle dot surrounded by a hot gaseous stream.
Permanent Link: https://hdl.handle.net/11104/0355053