The structure, stellar population, and formation history of the Milky Way’s nuclear star cluster

[EN] The center of the Milky Way is the only galactic nucleus and the most extreme astrophysical environment that we can examine on scales of milli- parsecs. It contains the nearest example of a nuclear star cluster (NSC). NSCs have been found at the photometric and dynamical centers of the majority...

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Detalles Bibliográficos
Autor: Gallego Cano, Eulalia
Tipo de recurso: tesis doctoral
Estado:Versión publicada
Fecha de publicación:2019
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/180946
Acceso en línea:http://hdl.handle.net/10261/180946
Access Level:acceso abierto
Palabra clave:Milky Way’s nuclear star cluster
Milky Way’s NSC
Vía Láctea: cúmulo estelar nuclear
Universo Local
Descripción
Sumario:[EN] The center of the Milky Way is the only galactic nucleus and the most extreme astrophysical environment that we can examine on scales of milli- parsecs. It contains the nearest example of a nuclear star cluster (NSC). NSCs have been found at the photometric and dynamical centers of the majority of galaxies in the local Universe. With e↵ective radii of a few parsecs and masses ranging between a few times 106–108 M!, they are among the densest known stellar structures. NSCs possess complex stellar populations and show clear signs of recurrent star formation, with the most recent event having occurred less than 100Myr ago in many of them. Moreover, NSCs can coexist with massive black holes (MBHs) at their centers. The Milky Way’s nuclear star cluster (MWNSC) is located at a mere 8 kpc from Earth. While we can only study the integrated light in extragalactic NSCs, we can in the case of the Galactic center (GC) resolve physical scales on the order of a few milliparsecs (mpc) and thus study the properties, kinematics and even dynamics of individual stars. We possess unambiguous evidence for the existence of a 4 ⇥ 106 M! central black hole at the center of the MWNSC, thus making it an ideal target to study the interaction between a dense stellar cluster and a massive black hole. Due to the unique observational challenges – extreme crowding and extinction – the study of the NSC at the GC is confronted with unique difficulties.