Related papers: A Radio Transient 0.1 pc from Sagittarius A*

We report the detection of the two-dimensional structure of the radio source associated with the Galactic Center black hole, Sagittarius A*, obtained from Very Long Baseline Array (VLBA) observations at a wavelength of 7mm. The intrinsic…

We report measurements with the Very Long Baseline Array of the proper motion of Sgr A* relative to two extragalactic radio sources spanning 18 years. The apparent motion of Sgr A* is -6.411 +/- 0.008 mas/yr along the Galactic plane and…

Proper motions and radial velocities of luminous infrared stars in the galactic center have provided strong evidence for a dark mass of 2.5 million solar masses in the central 0.05 pc of the galaxy. The leading hypothesis for this mass is a…

Most galactic nuclei are now believed to harbour supermassive black holes. Studies of stellar motions in the central few light-years of our Milky Way Galaxy indicate the presence of a dark object with a mass of about 2.6 million solar…

Recently, unprecedentedly accurate data on the orbital motion of stars in the vicinity of the Sagittarius $ {\rm A^*}$ have been available. Such information can be used not only to constrain the mass of the supermassive black hole (SMBH) in…

The radio sky is poorly sampled for rapidly varying transients because of the narrow field-of-view of most imaging radio telescopes at cm and shorter wavelengths. The emergence of sensitive long wavelength observations with intrinsically…

Recent measurements of stellar orbits provide compelling evidence that the compact radio source Sagittarius A* at the Galactic Centre is a 3.6-million-solar-mass black hole. Sgr A* is remarkably faint in all wavebands other than the radio…

Transient astronomical sources are typically powered by compact objects and usually signify highly explosive or dynamic events. While radio astronomy has an impressive record of obtaining high time resolution observations, usually it is…

We report the detection of a new radio transient source, GCRT J1746-2757, located only 1.1 degrees north of the Galactic center. Consistent with other radio transients toward the Galactic center, this source brightened and faded on a time…

We report the detection of a new transient radio source, GCRT J1742-3001, located ~1 degree from the Galactic center. The source was detected ten times from late 2006 to 2007 May in our 235 MHz transient monitoring program with the Giant…

We report the appearance of a new radio source at a projected offset of 460 pc from the nucleus of Cygnus A. The flux density of the source (which we designate Cygnus A-2) rose from an upper limit of <0.5 mJy in 1989 to 4 mJy in 2016…

We report the results of a survey of the Galactic Center region (|l| < 2deg, |b| < 0.5deg) performed with the BeppoSAX satellite. The flux from the center of our Galaxy corresponds to a luminosity of ~3 10^{35} erg/s in the 2-10 keV range.…

We present results of our Chandra observation with the ACIS-I instrument centered on the position of Sagittarius A* (Sgr A*), the compact nonthermal radio source associated with the massive black hole (MBH) at the dynamical center of the…

We have detected the intrinsic size of Sagittarius A*, the Galactic Center radio source associated with a supermassive black hole, showing that the short-wavelength radio emission arises from very near the event horizon of the black hole.…

Measurements of stellar orbits provide compelling evidence that the compact radio source Sagittarius A* at the Galactic Centre is a black hole four million times the mass of the Sun. With the exception of modest X-ray and infrared flares,…

We summarize the current state of polarization observations of Sagittarius A*, the compact radio source and supermassive black hole candidate in the Galactic Center. These observations are providing new tools for understanding accretion…

We report the discovery of a bright X-ray transient object, XMMU J174554.4-285456, observed in outburst with XMM-Newton on October 3, 2002,and located at 6.3' from SgrA*, the supermassive black hole at the Galactic center.This object…

We report the detection of Sagittarius A*, the radio source associated with our Galaxy's central massive black hole, at 330 MHz with the Very Large Array. Implications for the spectrum and emission processes of Sagittarius A* are discussed…

The enigmatic radio source Sagittarius A* at the centre of our Galaxy appears to be a low-luminosity version of active galactic nuclei in other galaxies. By analogy with active galactic nuclei models, it has been proposed that Sgr A* may be…

The center of our Galaxy hosts a supermassive black hole, Sagittarius (Sgr) A*. Young, massive stars within 0.5 pc of SgrA* are evidence of an episode of intense star formation near the black hole a few Myr ago, which might have left behind…