English
Related papers

Related papers: A strongly magnetized pulsar within grasp of the M…

200 papers

The compact radio source Sgr A* is coincident with a 4 million solar mass black hole at the dynamical center of the Galaxy and is surrounded by dense orbiting ionized and molecular gas. We present high resolution radio continuum images of…

High Energy Astrophysical Phenomena · Physics 2015-06-11 F. Yusef-Zadeh , R. Arendt , H. Bushouse , W. Cotton , D. Haggard , M. W. Pound , D. A. Roberts , M. Royster , M. Wardle

The center of the Milky Way hosts the closest supermassive black hole, SgrA$^*$. Decades of near-infrared observations of our Galactic Center have shown the presence of a small population of stars (the so called S-star cluster) orbiting…

Astrophysics of Galaxies · Physics 2022-06-29 Giacomo Fragione , Abraham Loeb

The region bounded by the inner tens of light years at the center of the Milky Way contains five principal components that coexist within the central deep gravitational potential well. These constituents are a black hole candidate (Sgr~A*)…

Astrophysics · Physics 2015-06-24 F. Yusef-Zade , F. Melia , M. Wardle

As a key science project of the Square Kilometre Array (SKA), the discovery and timing observations of radio pulsars in the Galactic Center would provide high-precision measurements of the spacetime around the supermassive black hole,…

High Energy Astrophysical Phenomena · Physics 2024-12-09 Zexin Hu , Lijing Shao

Starting in 2006, Swift has been targeting a region of ~21'X21' around Sagittarius A* (Sgr A*) with the onboard X-ray telescope. The short, quasi-daily observations offer an unique view of the long-term X-ray behavior of the supermassive…

High Energy Astrophysical Phenomena · Physics 2015-06-11 N. Degenaar , J. M. Miller , J. Kennea , N. Gehrels M. T. Reynolds , R. Wijnands

Recent studies have shown possible connections between highly magnetized neutron stars ("magnetars"), whose X-ray emission is too bright to be powered by rotational energy, and ordinary radio pulsars. In addition to the magnetar SGR…

High Energy Astrophysical Phenomena · Physics 2017-04-12 J. Dexter , N. Degenaar , M. Kerr , A. Deller , J. Deneva , P. Lazarus , M. Kramer , D. Champion , R. Karuppusamy

Sagittarius A* harbors the supermassive black hole that lies at the dynamical center of our Galaxy. Sagittarius A* spends most of its time in a low luminosity emission state but flares frequently in the infrared and X-ray, increasing up to…

Understanding the origin of the flaring activity from the Galactic center supermassive black hole, Sagittarius A*, is a major scientific goal of the NuSTAR Galactic plane survey campaign. We report on the data obtained between July 2012 and…

In 2006 February, shortly after its launch, Swift began monitoring the center of the Milky Way with the onboard X-Ray Telescope using short 1-ks exposures performed every 1-4 days. Between 2006 and 2014, over 1200 observations have been…

High Energy Astrophysical Phenomena · Physics 2015-03-27 N. Degenaar , R. Wijnands , J. M. Miller , M. T. Reynolds , J. Kennea , N. Gehrels

The gas cloud G2 falling toward Sagittarius A* (Sgr A*), the supermassive black hole at the center of the Milky Way, is supposed to provide valuable information on the physics of accretion flows and the environment of the black hole. We…

High Energy Astrophysical Phenomena · Physics 2015-04-22 J. -H. Park , S. Trippe , T. P. Krichbaum , J. -Y. Kim , M. Kino , A. Bertarini , M. Bremer , P. de Vicente

Radio and mm-wavelength observations of Sagittarius A* (Sgr A*), the radio source associated with the supermassive black hole at the center of our Galaxy, show that it behaves as a partially self-absorbed synchrotron-emitting source. The…

The Galactic Center (GC), with its high density of massive stars, is a promising target for radio transient searches. In particular, the discovery and timing of a pulsar orbiting the central supermassive black hole (SMBH) of our Galaxy will…

Observations of Sagittarius A* (Sgr A*) in near-infrared (NIR) show irregular flaring activity. Flares coincide with astrometric rotation of brightness centroid and with looping patterns in fractional linear polarization. These signatures…

High Energy Astrophysical Phenomena · Physics 2024-11-27 A. I. Yfantis , M. Wielgus , M. A. Mościbrodzka

We present 7 mm lambda VLBA observations of the compact nonthermal radio source in the Galactic Center, Sgr A*. These observations confirm the hypothesis that the image of Sgr A* is a resolved elliptical Gaussian caused by the scattering of…

Astrophysics · Physics 2009-10-30 Geoffrey C. Bower , Donald C. Backer

The compact radio source Sgr A*, believed to be the counterpart of the massive black hole at the Galactic nucleus, was observed to undergo rapid and intense flaring activity in X-rays with Chandra in October 2000. We report here the…

Astrophysics · Physics 2009-11-07 A. Goldwurm , E. Brion , P. Goldoni , P. Ferrando , F. Daigne , A. Decourchelle , R. S. Warwick , P. Predehl

Context: The supermassive black hole at the Galactic center, SgrA*, shows frequent radiation outbursts, often called 'flares'. In the near-infrared some of these flares were reported as showing intrinsic quasi-periodicities. The flux peaks…

Astrophysics · Physics 2009-11-11 L. Meyer , R. Schoedel , A. Eckart , V. Karas , M. Dovciak , W. J. Duschl

This paper presents the Suzaku results obtained for the Sagittarius (Sgr) C region using the concept of X-ray reflection nebulae (XRNe) as the echo of past flares from the super massive black hole, Sgr A*. The Sgr C complex is composed of…

Astrophysics of Galaxies · Physics 2016-03-02 Syukyo Gando Ryu , Masayoshi Nobukawa , Shinya Nakashima , Takeshi Go Tsuru , Katsuji Koyama , Hideki Uchiyama

In spite of increasing evidences of the presence of a massive Black Hole at the Galactic Center, its radio counterpart, Sgr A*, shows little activity at high energies, and recent models involving energy advection (ADAF) have been proposed…

Astrophysics · Physics 2007-05-23 A. Goldwurm , P. Goldoni , P. Laurent , F. Lebrun , J. Paul

The compact radio source at the center of our Galaxy, Sagittarius A* (Sgr A*), is the subject of intensive study as it provides a close-up view of an accreting supermassive black hole. Sgr A* provides us with a prototype of a low-luminosity…

High Energy Astrophysical Phenomena · Physics 2021-07-29 Christiaan Brinkerink , Heino Falcke , Andreas Brunthaler , Casey Law

Sgr A*, the supermassive black hole at the center of the Milky Way, exhibits frequent short-duration flares with luminosity greater than 1e34 erg/s across multiple wavelengths. The origin of the flares is still unknown. We revisited the…

High Energy Astrophysical Phenomena · Physics 2025-12-02 Wen-Han Zhou , Yun Zhang , Jiamu Huang , Douglas N. C. Lin