Galactic Center Research: Manifestations of the Central Black Hole

Abstract

This review summarizes a few of the frontiers of Galactic center research that are currently the focus of considerable activity and attention. It is aimed at providing a necessarily incomplete sketch of some of the timely work being done on phenomena taking place in, or originating in, the central few parsecs of the Galaxy, with particular attention to topics related to the Galactic black hole (GBH). We have chosen to expand on the following exciting topics: 1) the characterization and the implications for the variability of emission from the GBH, 2) the strong evidence for a powerful X-ray flare in the Galactic center within the past few hundred years, and the likelihood that the GBH is implicated in that event, 3) the prospects for detecting the "shadow" of the GBH, 4) an overview of the current state of research on the central S-star cluster, and what has been learned from the stellar orbits within that cluster, and 5) the current hypotheses for the origin of the G2 dust cloud that is projected to make a close passage by the GBH in 2013.

Review article, in press with Review of Astronomy and Astrophysics

References in corpus (20)

• Event-horizon-scale structure in the supermassive black hole candidate at the Galactic Centre
• Testing the general relativistic ''no-hair'' theorems using the galactic center black hole SgrA*
• Polarimetry of near-infrared flares from Sagittarius A*
• Flaring Activity of Sgr A* at 43 and 22 GHz: Evidence for Expanding Hot Plasma
• Dynamics of Ionized Gas at the Galactic Center: VLA Observations of the 3D Velocity Field and Location of the Ionized Streams in Sagittarius A West
• X-ray hiccups from SgrA* observed by XMM-Newton. The second brightest flare and three moderate flares caught in half a day
• The Origin of Diffuse X-ray and $\gamma$-ray Emission from the Galactic Center Region: Cosmic Ray Particles
• A polarised infrared flare from Sagittarius A* and the signatures of orbiting plasma hotspots
• Simultaneous Chandra, CSO and VLA Observations of Sgr A*: The Nature of Flaring Activity
• Near-infrared polarimetry setting constraints on the orbiting spot model for Sgr A* flares
• Dynamical evolution of the young stars in the Galactic center: N-body simulations of the S-stars
• Discovery of Variable Iron Fluorescence from Reflection Nebulae in the Galactic Center
• K-band polarimetry of an Sgr A* flare with a clear sub-flare structure
• Simultaneous NIR/sub-mm observation of flare emission from SgrA*
• The X-ray lightcurve of Sgr A* over the past 150 years inferred from Fe-Ka line reverberation in Galactic Centre molecular clouds
• A 600 minute near-infrared lightcurve of Sagittarius A*
• On the orientation of the Sagittarius A* system
• A power-law break in the near-infrared power spectrum of the Galactic center black hole
• Observing a Black Hole Event Horizon: (Sub)Millimeter VLBI of Sgr A*
• A New Supernova Remnant Candidate and an Associated Outflow in the Sagittarius C Region

Cited by in corpus (50)

• The Galaxy in Context: Structural, Kinematic and Integrated Properties
• Detection of the gravitational redshift in the orbit of the star S2 near the Galactic centre massive black hole
• First Sagittarius A* Event Horizon Telescope Results. VI: Testing the Black Hole Metric
• Detection of the Schwarzschild precession in the orbit of the star S2 near the Galactic centre massive black hole
• First Sagittarius A* Event Horizon Telescope Results. II. EHT and Multi-wavelength Observations, Data Processing, and Calibration
• Shadow of a Kaluza-Klein rotating dilaton black hole
• Merging Binaries in the Galactic Center: The eccentric Kozai-Lidov mechanism with stellar evolution
• Constraints on a charge in the Reissner--Nordström metric for the black hole at the Galactic Center
• Towards the event horizon -- the supermassive black hole in the Galactic Center
• The XMM-Newton view of the central degrees of the Milky Way
• Variability Timescale and Spectral Index of Sgr A* in the Near Infrared: Approximate Bayesian Computation Analysis of the Variability of the Closest Supermassive Black Hole
• Unprecedented variability of Sgr A* in NIR
• Stellar transits across a magnetized accretion torus as a mechanism for plasmoid ejection
• An 8 hour characteristic time-scale in submillimetre light curves of Sagittarius A*
• Gravitational lensing by massless braneworld black holes
• Free motion around black holes with discs or rings: between integrability and chaos - II
• Rapid Variability of Sgr A* across the Electromagnetic Spectrum
• Regular phantom black hole gravitational lensing
• Constraints on tidal charge of the supermassive black hole at the Galactic Center with trajectories of bright stars
• $f(R)$-gravity after the detection of the orbital precession of the S2 star around the Galactic centre massive black hole
• Kerr black hole parameters in terms of red/blue shifts of photons emitted by geodesic particles
• Clustering of Local Group distances: publication bias or correlated measurements? IV. The Galactic Center
• Recent advances in the determination of some Galactic constants in the Milky Way
• Free motion around black holes with discs or rings: between integrability and chaos - III
• Null Geodesics and Observables around Kerr-Sen Black Hole
• Simultaneous X-ray and Infrared Observations of Sagittarius A*'s Variability
• Polarimetric signatures of hot spots in black hole accretion flows
• Diffuse X-Ray Sky in the Galactic Center
• Exploring plasma evolution during Sagittarius A* flares
• Strong deflection lensing by charged black holes in scalar-tensor gravity
• Multiwavelength Light Curves of Two Remarkable Sagittarius A* Flares
• Obtaining mass parameters of compact objects from red-blue shifts emitted by geodesic particles around them
• The black hole at the Galactic Center: observations and models
• Second Scale Submillimeter Variability of Sagittarius A* during flaring activity of 2019: On the Origin of Bright Near Infrared Flares
• Star Formation and Dynamics in the Galactic Centre
• Testing Chern-Simons gravity with black holes?
• Simultaneous Monitoring of X-ray and Radio Variability in Sagittarius A*
• Mass and spin of Kerr black holes in terms of observational quantities: The dragging effect on the redshift
• Toward the Gravitational Redshift Detection in NGC 4258 and the Estimation of its Black Hole Mass-to-Distance Ratio
• Fermi LAT observations of Sagittarius A*: Imaging Analysis
• Dynamics and Emission Properties of Flux Ropes from Two-Temperature GRMHD Simulations with Multiple Magnetic Loops
• A Swift study of long-term changes in the X-ray flaring properties of Sagittarius A*
• Observational redshift from general spherically symmetric black holes
• The impact of gravitational lensing in the reconstruction of stellar orbits around Sgr A*
• Schwarzschild black hole and redshift rapidity: A new approach towards measuring cosmic distances
• S0-2 star, G1- and G2-objects and flaring activity of the Milky Way's Galactic Center black hole in 2019
• Advancing the Physics of Cosmic Distances: Conference Summary
• MOLsphere and pulsations of the Galactic Center's red supergiant GCIRS 7 from VLTI/GRAVITY
• General relativistic formulas for mass and spin of a Kerr black hole in terms of redshifts and orbital parameters
• Thermodynamic and observational implications of black holes in toroidal geometry