The nuclear cluster of the Milky Way: Our primary testbed for the interaction of a dense star cluster with a massive black hole

Abstract

This article intends to provide a concise overview, from an observational point-of-view, of the current state of our knowledge of the most relevant properties of the Milky Way's nuclear star cluster (MWNSC). The MWNSC appears to be a typical specimen of nuclear star clusters, which are found at the centers of the majority of all types of galaxies. Nuclear clusters represent the densest and most massive stellar systems in the present-day Universe and frequently coexist with central massive black holes. They are therefore of prime interest for studying stellar dynamics and the MWNSC is the only one that allows us to obtain data on milli-parsec scales. After discussing the main observational constraints, we start with a description of the overall structure and kinematics of the MWNSC, then focus on a comparison to extragalactic systems, summarize the properties of the young, massive stars in the immediate environment of the Milky Way's central black hole, Sagittarius\,A*, and finally focus on the dynamics of stars orbiting the black hole at distances of a few to a few tens of milli parsecs.

accepted for publication in Classical and Quantum Gravity as a Special Issue Article

References in corpus (26)

• The SAURON project -- IX. A kinematic classification for early-type galaxies
• The Two Young Star Disks in the Central Parsec of the Galaxy: Properties, Dynamics and Formation
• Intermediate and Extreme Mass-Ratio Inspirals -- Astrophysics, Science Applications and Detection using LISA
• The ACS Virgo Cluster Survey. VIII. The Nuclei of Early-Type Galaxies
• Starbursts near supermassive black holes: young stars in the Galactic Center, and gravitational waves in LISA band
• Testing the general relativistic ''no-hair'' theorems using the galactic center black hole SgrA*
• The structure of the nuclear stellar cluster of the Milky Way
• The Coincidence of Nuclear Star Clusters and Active Galactic Nuclei
• The AIMSS Project I: Bridging the Star Cluster - Galaxy Divide
• Nuclear star clusters in 228 spiral galaxies in the HST/WFPC2 archive: catalogue and comparison to other stellar systems
• Stellar Proper Motions in the Galactic Bulge from deep HST ACS/WFC Photometry
• Clues to Nuclear Star Cluster Formation from Edge-on Spirals
• Chemical Abundances of Luminous Cool Stars in the Galactic Center from High-Resolution Infrared Spectroscopy
• Large scale kinematics and dynamical modelling of the Milky Way nuclear star cluster
• Kinematics of the old stellar population at the Galactic Center
• Evidence for a Long-Standing Top-Heavy IMF in the Central Parsec of the Galaxy
• Dynamical evolution of the young stars in the Galactic center: N-body simulations of the S-stars
• Periapsis and gravitomagnetic precessions of stellar orbits in Kerr and Kerr-de Sitter black hole spacetimes
• On the nature of the fast moving star S2 in the Galactic Center
• Red giant stellar collisions in the Galactic Centre
• Dynamical Constraints on The Masses of the Nuclear Star Cluster and Black Hole in the Late-Type Spiral Galaxy NGC 3621
• The complex, variable near infrared extinction towards the Nuclear Bulge
• The S-Star Cluster at the Center of the Milky Way: On the nature of diffuse NIR emission in the inner tenth of a parsec
• Cluster Core Dynamics at the Galactic Center
• Relativistic dynamics of stars near a supermassive black hole
• Radial Velocities of Stars in the Galactic Center

Cited by in corpus (61)

• Nuclear Star Clusters
• The TianQin project: current progress on science and technology
• Science with the TianQin observatory: Preliminary result on extreme-mass-ratio inspirals
• The Milky Way's nuclear star cluster: Old, metal-rich, and cuspy
• Dark matter spikes in the vicinity of Kerr black holes
• Stellar transits across a magnetized accretion torus as a mechanism for plasmoid ejection
• KMOS view of the Galactic Centre - II. Metallicity distribution of late-type stars
• A deep view into the nucleus of the Sagittarius Dwarf Spheroidal Galaxy with MUSE. I. Data and stellar population characterization
• New constraints on the structure of the nuclear stellar cluster of the Milky Way from star counts and MIR imaging
• Preparing the next gravitational million-body simulations: Evolution of single and binary stars in Nbody6++GPU, MOCCA and McLuster
• X-MRIs: Extremely Large Mass-Ratio Inspirals
• Analytical models of supermassive black holes in galaxies surrounded by dark matter halos
• Discovery of RR Lyrae Stars in the Nuclear Bulge of the Milky Way
• Detection of astrophysical gravitational wave sources by TianQin and LISA
• Steeper stellar cusps in galactic centers from binary disruption
• Formation of supermassive black hole seeds in nuclear star clusters via gas accretion and runaway collisions
• Making massive stars in the Galactic Centre via accretion onto low-mass stars within an accretion disc
• Asymmetric spatial distribution of sub-solar metallicity stars in the Milky Way nuclear star cluster
• Higgs portals to pulsar collapse
• Gravitational redshift/blueshift of light emitted by geodesic test particles, frame-dragging and pericentre-shift effects, in the Kerr-Newman-de Sitter and Kerr-Newman black hole geometries
• The Galactic Center: Improved Relative Astrometry for Velocities, Accelerations, and Orbits near the Supermassive Black Hole
• Near-Infrared Variability Study of the Central 2.3 arcmin x 2.3 arcmin of the Galactic Centre II. Identification of RR Lyrae Stars in the Milky Way Nuclear Star Cluster
• Massive black hole assembly in nuclear star clusters
• Massive binary star mergers in galactic nuclei: implications for blue stragglers, binary S-stars and gravitational waves
• The nuclear star cluster and nuclear stellar disc of the Milky Way: Different stellar population and star formation history
• Extreme-mass-ratio burst detection with TianQin
• Global instability by runaway collisions in nuclear stellar clusters: Numerical tests of a route for massive black hole formation
• Mira variables in the Milky Way's nuclear stellar disc: discovery and classification
• Depletion of bright red giants in the Galactic center during its active phases
• Effect of mass loss due to stellar winds on the formation of supermassive black hole seeds in dense nuclear star clusters
• Constraints on the Galactic Centre environment from Gaia hypervelocity stars
• Star formation at the Galactic Centre: coevolution of multiple young stellar discs
• The extinction law in the inner $3\times 3$ deg${}^2$ of the Milky Way and the red clump absolute magnitude in the inner bar-bulge
• A proper motion catalogue for the Milky Way's nuclear stellar disc
• The formation history of our Galaxy's nuclear stellar disc constrained from HST observations of the Quintuplet field
• A new bow-shock source with bipolar morphology in the vicinity of Sgr A*
• Constraining the accretion flow density profile near Sgr A* using the $L^{\prime }$-band emission of the S2 star
• First results from a large-scale proper motion study of the Galactic Centre
• Transient stellar collisions as multimessenger probes: Non-thermal-, gravitational wave emission and the cosmic ladder argument
• Stellar Populations in the Transition Region of Nuclear Star Cluster and Nuclear Stellar Disc
• Orbits of globular clusters computed with dynamical friction in the Galactic anisotropic velocity dispersion field
• Close stellar encounters at the Galactic Centre I: The effect on the observed stellar populations
• Kinematic data rebuild the Nuclear star cluster as the most metal rich region of the Galaxy
• Constraints on the Galactic Centre environment from \textit{Gaia} hypervelocity stars III: Insights on a possible companion to Sgr A*
• Constraints on the Galactic Centre environment from Gaia hypervelocity stars II: The evolved population
• Efficiency of black hole formation via collisions in stellar systems: An analysis of data from simulations and observations
• The Inner 2 pc of Sagittarius A*: Simulations of the Circumnuclear Disk and Multiphase Gas Accretion in the Galactic Center
• Smooth kinematic and metallicity gradients reveal that the Milky Way's nuclear star cluster and disc might be part of the same structure
• Astrometry in crowded fields towards the Galactic Bulge
• Mid-Infrared studies of dusty sources in the Galactic Center
• Measuring the alpha-abundance of subsolar-metallicity stars in the Milky Way's central half-parsec: testing globular cluster and dwarf galaxy infall scenarios
• Growing a nuclear star cluster from star formation and cluster mergers: The JWST NIRSpec view of NGC 4654
• Millisecond Pulsars in Dense Star Clusters: Evolution, Scaling Relations, and the Galactic-Center Gamma-ray Excess
• Searching for clues of past binary supermassive black hole mergers in nuclear star clusters
• Red giant - jet collisions in galactic nuclei I: 3D hydrodynamical model of a few stellar orbits
• A study of the central stellar populations of galaxies in SDSS-IV MaNGA: identification of a sub-sample with unusually young and massive stars
• The JWST-NIRCam View of Sagittarius C. III. The Extinction Curve
• Chemical analysis of the Milky Way's Nuclear Star Cluster: Evidence for a metallicity gradient
• Age and metallicity of the Milky Way's nuclear star cluster studied at 3 pc from Sagittarius A*
• Constructing a gravitational wave analysis pipeline for extremely large mass ratio inspirals
• Supergiant GCIRS 22 in the Milky Way Nuclear Star Cluster: Revised alpha abundances