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Related papers: Bright X-ray flares from Sgr A*

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In recent years the case for the presence of 3-4 10^6 M_sun black hole in our Galactic Center has gained strength from results of stellar dynamics observations and from the detection of several rapid X-ray and IR flares observed in the…

Astrophysics · Physics 2008-11-26 A. Cadez , M. Calvani , A. Gomboc , U. Kostic

The cores of most galaxies are thought to harbour supermassive black holes, which power galactic nuclei by converting the gravitational energy of accreting matter into radiation (ref 1). Sagittarius A*, the compact source of radio, infrared…

Starting in 2012, we began an unprecedented observational program focused on the supermassive black hole in the center of our Galaxy, Sgr A*, utilizing the High Energy Transmission Gratings Spectrometer (HETGS) instrument on the Chandra…

High Energy Astrophysical Phenomena · Physics 2015-06-11 M. A. Nowak , J. Neilsen , S. B. Markoff , F. K. Baganoff , D. Porquet , N. Grosso , Y. Levin , J. Houck , A. Eckart , H. Falcke , L. Ji , J. M. Miller , Q. D. Wang

The compact radio source Sagittarius A (Sgr A) at the centre of our Galaxy harbours a supermassive black hole, whose mass has been measured from stellar orbital motions. Sgr A is therefore the nearest laboratory where super-massive black…

High Energy Astrophysical Phenomena · Physics 2009-03-24 U. Kostic , A. Cadez , M. Calvani , A. Gomboc

We report on a successful, simultaneous observation and modelling of the millimeter (mm) to near-infrared (NIR) flare emission of the Sgr A* counterpart associated with the supermassive black hole at the Galactic centre (GC). We present a…

Aims. We report on simultaneous observations and modeling of mid-infrared (MIR), near-infrared (NIR), and submillimeter (submm) emission of the source Sgr A* associated with the supermassive black hole at the center of our Galaxy. Our goal…

Astrophysics of Galaxies · Physics 2013-01-22 X. Haubois , K. Dodds-Eden , A. Weiss , T. Paumard , G. Perrin , Y. Clénet , S. Gillessen , P. Kervella , F. Eisenhauer , R. Genzel , D. Rouan

Studies of the inner few parsecs at the Galactic Centre provide evidence of a supermassive black hole, associated with the unusual, variable radio and infrared source Sgr A*. Our major aim is the study and analysis of the physical processes…

High Energy Astrophysical Phenomena · Physics 2016-02-03 E. M. Howard

We have analysed the light curve of the two brightest X-ray flares from the Galactic Center black hole, one flare observed by XMM-Newton on October 3, 2002 (Porquet et al. 2003), and the other flare observed by Chandra on October 26, 2000…

Astrophysics · Physics 2009-11-10 B. Aschenbach , N. Grosso , D. Porquet , P. Predehl

We discuss mm-wavelength radio, 2.2-11.8um NIR and 2-10 keV X-ray light curves of the super massive black hole (SMBH) counterpart of Sagittarius A* (SgrA*) near its lowest and highest observed luminosity states. The luminosity during the…

Stellar dynamics indicate the presence of a super massive 3-4x10^6 Msun solm black hole at the Galactic Center. It is associated with the variable radio, near-infrared, and X-ray counterpart Sagittarius A* (SgrA*). The goal is the…

The recent detection of variable infrared emission from Sagittarius A*, combined with its previously observed flare activity in X-rays, provides compelling evidence that at least a portion of this object's emission is produced by nonthermal…

Astrophysics · Physics 2009-11-10 Siming Liu , Vahe' Petrosian , Fulvio Melia

We present the first systematic analysis of the X-ray variability of Sgr A* during the Chandra X-ray Observatory's 2012 Sgr A* X-ray Visionary Project (XVP). With 38 High Energy Transmission Grating Spectrometer (HETGS) observations spaced…

The supermassive black hole, Sagittarius A* (Sgr A*), at the centre of the Milky Way undergoes regular flaring activity which is thought to arise from the innermost region of the accretion flow. We performed the monitoring observations of…

In recent years, near-IR and X-ray flares have been detected from the Galaxy's central radio point source, Sagittarius A* (Sgr A*), believed to be a \~3.10^6 solar masses supermassive black hole. In some cases, the transient emission…

Astrophysics · Physics 2009-11-13 Michel Tagger , Fulvio Melia

Emission from Sgr A* is highly variable at both X-ray and infrared (IR) wavelengths. Observations over the last ~20 years have revealed X-ray flares that rise above a quiescent thermal background about once per day, while faint X-ray flares…

High Energy Astrophysical Phenomena · Physics 2021-04-21 H. Boyce , D. Haggard , G. Witzel , S. P. Willner , J. Neilsen , J. L. Hora , S. Markoff , G. Ponti , F. Baganoff , E. Becklin , G. Fazio , P. Lowrance , M. R. Morris , H. A. Smith

Flares from the supermassive black hole in our Galaxy, Sagittarius~A$^\star$ (Sgr A$^\star$), are routinely observed over the last decade or so. Despite numerous observational and theoretical efforts, the nature of such flares still remains…

High Energy Astrophysical Phenomena · Physics 2017-07-19 Ya-Ping Li , Feng Yuan , Q. Daniel Wang

Variable emission from Sgr~A*, the luminous counterpart to the super-massive black hole at the center of our Galaxy, arises from the innermost portions of the accretion flow. Better characterization of the variability is important for…

High Energy Astrophysical Phenomena · Physics 2016-07-06 Jordan M. Stone , D. P. Marrone , C. D. Dowell , B. Schulz , C. O. Heinke , F. Yusef-Zadeh

Daily X-ray flaring represents an enigmatic phenomenon of Sgr A$^{\star}$ --- the supermassive black hole at the center of our Galaxy. We report initial results from a systematic X-ray study of this phenomenon, based on extensive {\it…

High Energy Astrophysical Phenomena · Physics 2015-12-29 Qiang Yuan , Q. Daniel Wang

The centre of the Milky Way hosts a supermassive black hole of 4 million solar masses called Sagittarius A*. This object has been observed for more than 20 years in the near infrared. This has confirmed some effects of General Relativity.…

High Energy Astrophysical Phenomena · Physics 2024-01-02 Aimar Nicolas

The Galactic Center black hole Sgr A* shows significant variability and flares in the submillimeter, infrared, and X-ray wavelengths. Owing to its exquisite resolution in the IR bands, the GRAVITY experiment for the first time spatially…

High Energy Astrophysical Phenomena · Physics 2021-08-18 David Ball , Feryal Özel , Pierre Christian , Chi-Kwan Chan , Dimitrios Psaltis