Related papers: The Galactic Center
Near a black hole, differential rotation of a magnetized accretion disk is thought to produce an instability that amplifies weak magnetic fields, driving accretion and outflow. These magnetic fields would naturally give rise to the observed…
We have reconstructed possible orbits for a collection of stars located within 0.5 arcsec of Sgr A*. These orbits are constrained by observed stellar positions and angular proper motions. The construction of such orbits serves as a baseline…
The long-standing issues of determination of the mass distribution and nature of the center of our Galaxy could be probed by a lensing experiment capable of testing the spatial and velocity distributions of stars nearby and beyond it. We…
Sagittarius A* is the source of near infrared, X-ray, radio, and (sub)millimeter emission associated with the supermassive black hole at the Galactic Center. In the submillimeter regime, Sgr A* exhibits time-variable linear polarization on…
This is a pedagogical review of recent results on the interactions of central massive black holes with stars very near them, focused on the black hole in the center of the Milky Way. Table of contents: [1] Introduction [2] Stellar dynamics…
We present a wide field, sub-arcminute resolution VLA image of the Galactic Center region at 330 MHz. With a resolution of ~ 7" X 12" and an RMS noise of 1.6 mJy/beam, this image represents a significant increase in resolution and…
The Galactic Center shows evidence for the presence of three important AGN ingredients: a Black Hole ($M_\bullet\sim10^6M_\odot$), an accretion disk ($10^{-8.5} - 10^{-7} M_\odot/{\rm yr}$) and a powerful jet (jet power $\ge$ 10\% disk…
We report on the polarized light curves of the Galactic Center supermassive black hole Sagittarius A*, obtained at millimeter wavelength with the Atacama Large Millimeter/submillimeter Array (ALMA). The observations took place as a part of…
Sub milli-arcsecond astrometry and imaging of the black hole Sgr A* at the Galactic centre may become possible in the near future at infrared and sub-millimetre wavelengths. Motivated by observations of short-term infrared and X-ray…
Stellar orbits at the Galactic Center provide a very clean probe of the gravitational potential of the supermassive black hole. They can be studied with unique precision, beyond the confusion limit of a single telescope, with the…
The magnetar SGR J1745-2900 discovered at parsecs distance from the Milky Way central black hole, Sagittarius A*, represents the closest pulsar to a supermassive black hole ever detected. Furthermore, its intriguing radio emission has been…
We report the discovery of molecular gas streams orbiting around an invisible massive object in the central region of our Galaxy, based on the high-resolution molecular line observations with the Atacama Large Millimeter/submillimeter Array…
Nuclear star clusters (NSCs) are located at the photometric and dynamical centers of the majority of galaxies. They are among the densest star clusters in the Universe. The NSC in the Milky Way is the only object of this class that can be…
The existence of stellar cusps in dense clusters around massive black holes is a fundamental, decades-old prediction of theoretical stellar dynamics. Yet, observational evidence has been difficult to obtain. With a new, improved analysis of…
Pulsars orbiting the Galactic center black hole, Sgr A*, would be potential probes of its mass, distance and spin, and may even be used to test general relativity. Despite predictions of large populations of both ordinary and millisecond…
Studying the orbital motion of stars around Sagittarius A* in the Galactic Center provides a unique opportunity to probe the gravitational potential near the supermassive black hole at the heart of our Galaxy. Interferometric data obtained…
We present preliminary results of our \hst Pa$\alpha$ survey of the Galactic Center (\gc), which maps the central 0.65$\times$0.25 degrees around Sgr A*. This survey provides us with a more complete inventory of massive stars within the…
The linearly polarized millimeter and sub-millimeter emission in Sagittarius A* is produced within 10 Schwarzschild radii of the supermassive black hole at the Galactic Center and may originate from a hot magnetized accretion disk, where…
We study the dynamical evolution of stars and gas close to the centre of the Milky Way. Any plausible means of forming the young stars observed at the Galactic Centre leaves behind a residual gas disc at ~0.01pc radii. We show that the…
Investigating the spectral and temporal characteristics of the X-rays coming from Sagittarius A* (Sgr A*) is essential to our development of a more complete understanding of the emission mechanisms in this supermassive black hole located at…