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Related papers: A "coronal-mass-ejection'' model for flares in Sag…

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Sagittarius A* (Sgr A*) exhibits frequent flaring activity across the electromagnetic spectrum, often associated with a localized region of strong emission, known as a hot spot. We aim to establish an empirical relationship linking key…

High Energy Astrophysical Phenomena · Physics 2026-02-25 A. I. Yfantis , D. C. M. Palumbo , M. Mościbrodzka

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

Sgr A*, the putative black hole in our Galactic Center (GC), is extraordinary dim in all frequencies. Apparently the black hole is unable to accrete at the Bondi accretion rate for some reason. Another mystery of Sgr A* is the recently…

Astrophysics · Physics 2009-11-07 Sergei Nayakshin , Jorge Cuadra , Rashid Sunyaev

Sagittarius A* (Sgr A*) is the supermassive black hole residing at the center of the Milky Way. It has been the main target of an extensive multiwavelength campaign we carried out in April 2007. Herein, we report the detection of a bright…

High Energy Astrophysical Phenomena · Physics 2014-11-20 G. Trap , A. Goldwurm , R. Terrier , K. Dodds-Eden , S. Gillessen , R. Genzel , E. Pantin , P. O. Lagage , P. Ferrando , G. Belanger , D. Porquet , N. Grosso , F. Yusef-Zadeh , F. Melia

The source of emission from Sgr A*, the supermassive black hole at the Galactic Center, is still unknown. Flares and data from multiwavelength campaigns provide important clues about the nature of Sgr A* itself. Here we attempt to constrain…

Astrophysics of Galaxies · Physics 2015-05-14 Dipankar Maitra , Sera Markoff , Heino Falcke

In 2019, Sgr A* - the supermassive black hole in the Galactic Center - underwent unprecedented flaring activity in the near infrared (NIR), brightening by up to a factor of 100 compared to quiescent values. Here we report ALMA observations…

Astrophysics of Galaxies · Physics 2021-10-13 Lena Murchikova , Gunther Witzel

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

Sagittarius A* (Sgr A*) is a compact radio source at the Galactic center. Observations have confirmed that its mass is approximately (4.1)*10$^{6}$ M$_{\odot}$, and Sgr A* is generally believed to be powered by gas accretion onto a…

High Energy Astrophysical Phenomena · Physics 2026-03-05 Shenyue Yin , Siming Liu

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…

Sgr A* exhibits flares in the near-infrared and X-ray bands, with the luminosity in these bands increasing by factors of $10-100$ for $\approx 60$ minutes. One of the models proposed to explain these flares is synchrotron emission of…

High Energy Astrophysical Phenomena · Physics 2022-02-16 Nicolas Scepi , Jason Dexter , Mitchell C. Begelman

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

The radio source Sagittarius A* (Sgr A*), is thought to be a supermassive black hole located at the centre of our Galaxy, that is accreting gas from the surrounding region. Using the high inferred accretion rates, however, standard…

Astrophysics · Physics 2007-05-23 Rohan Mahadevan

The supermassive black hole Sgr A* at the center of our galaxy produces repeating near-infrared flares that are observed by ground and space based instruments. This activity has been simulated in the past with Magnetically Arrested Disk…

High Energy Astrophysical Phenomena · Physics 2024-09-11 I. Dimitropoulos , A. Nathanail , M. Petropoulou , I. Contopoulos , C. M. Fromm

Sgr A* exhibits flaring in the infrared several times each day, occasionally accompanied by flaring in X-rays. The infrared flares are believed to arise through synchrotron emission from a transient population of accelerated electrons. The…

Astrophysics of Galaxies · Physics 2010-07-13 Mark Wardle

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…

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

The GRAVITY interferometer has achieved microarcsecond precision in near-infrared interferometry, enabling the tracking of flare centroid motion in the strong gravitational field near the Sgr A*. It might be promising to serve as a unique…

High Energy Astrophysical Phenomena · Physics 2026-01-09 Fengting Xie , Qing-Hua Zhu , Xin Li

High-resolution, multi-wavelength, and time-domain observations of the Galactic centre black hole candidate, Sgr A*, allow for a direct test of contemporary accretion theory. To date, all models have assumed alignment between the accretion…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Jason Dexter , P. Chris Fragile

Context: We report new polarization measurements of the variable near-infrared emission of the SgrA* counterpart associated with the massive 3--4 10^6 solar masses Black Hole at the Galactic Center. Aims: We investigate the physical…

Astrophysics · Physics 2009-11-11 A. Eckart , R. Schoedel , L. Meyer , S. Trippe , T. Ott , R. Genzel