English
Related papers

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

200 papers

High-resolution observations with GRAVITY-VLTI instrument have provided abundant information about the flares in Sgr A*, the supermassive black hole in our Galactic center, including the time-dependent location of the centroid (a "hot…

High Energy Astrophysical Phenomena · Physics 2024-05-28 Lin Xi , Yuan Feng

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

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

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

Sagittarius A*, the supermassive black hole at the center of our galaxy, exhibits episodic near-infrared flares. The recent monitoring of three such events by the GRAVITY instrument has shown that some flares are associated with orbital…

High Energy Astrophysical Phenomena · Physics 2023-04-05 N. Aimar , A. Dmytriiev , F. H. Vincent , I. El Mellah , T. Paumard , G. Perrin , A. Zech

We use a model of an accretion flow coupled with an emergent flare to interpret the latest 1.3mm VLBI measurements for Sagittarius A*. The visibility data constrained the distances from the flare center to the black hole center as $d_{\rm…

Astrophysics of Galaxies · Physics 2015-06-03 Lei Huang , Zhi-Qiang Shen , Feng Gao

The emission from Sgr A*, the supermassive black hole in the Galactic Center, shows order of magnitude variability ("flares") a few times a day that is particularly prominent in the near-infrared (NIR) and X-rays. We present a…

X-ray flares have routinely been observed from the supermassive black hole, Sagittarius A$^\star$ (Sgr A$^\star$), at our Galactic center. The nature of these flares remains largely unclear, despite of many theoretical models. In this…

High Energy Astrophysical Phenomena · Physics 2015-09-16 Ya-Ping Li , Feng Yuan , Qiang Yuan , Q. Daniel Wang , P. F. Chen , Joseph Neilsen , Taotao Fang , Shuo Zhang , Jason Dexter

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…

Astrophysics · Physics 2009-11-10 R. Genzel , R. Schoedel , T. Ott , A. Eckart , T. Alexander , F. Lacombe , D. Rouan , B. Aschenbach

The interaction between the supermassive black hole at the center of the Milky Way, Sagittarius A*, and its accretion disk occasionally produces high-energy flares seen in X-ray, infrared, and radio. One proposed mechanism that produces…

High Energy Astrophysical Phenomena · Physics 2024-04-18 Aviad Levis , Andrew A. Chael , Katherine L. Bouman , Maciek Wielgus , Pratul P. Srinivasan

Sagittarius~A$^*$, the supermassive black hole at the center of our galaxy, exhibits flares across various wavelengths, yet their origins remain elusive. We performed 3D two-temperature General Relativistic Magnetohydrodynamic (GRMHD)…

High Energy Astrophysical Phenomena · Physics 2025-07-18 Hong-Xuan Jiang , Yosuke Mizuno , Indu K. Dihingia , Feng Yuan , Xi Lin , Christian M. Fromm , Antonios Nathanail , Ziri Younsi

Infrared observations of Sgr A* probe the region close to the event horizon of the black hole at the Galactic center. These observations can constrain the properties of low-luminosity accretion as well as that of the black hole itself. The…

Low-luminosity supermassive and stellar-mass black holes (BHs) may be embedded in a collisionless and highly magnetized plasma. They show non-thermal flares indicative of efficient dissipative processes in the vicinity of the BH. During NIR…

High Energy Astrophysical Phenomena · Physics 2023-09-13 I. El Mellah , B. Cerutti , B. Crinquand

We address a question whether the observed light curves of X-ray flares originating deep in galactic cores can give us independent constraints on the mass of the central supermassive black hole. To this end we study four brightest flares…

Astrophysics of Galaxies · Physics 2017-10-18 G. D. Karssen , M. Bursa , A. Eckart , M. Valencia-S. , M. Dovciak , V. Karas , J. Horak

Energetic flares are observed in the Galactic supermassive black hole Sagittarius A* from radio to X-ray wavelengths. On a few occasions, simultaneous flares have been detected in IR and X-ray observations, but clear counterparts at longer…

Episodically accreting black holes are thought to produce flares when a chunk of particles is accelerated to high velocity near the black hole horizon. This also seems to be the case of Sagittarius A* in the Galactic Center, where the…

Astrophysics · Physics 2009-07-17 V. Karas , M. Dovciak , A. Eckart , L. Meyer

Recent observations of SgrA* by the GRAVITY instrument have astrometrically tracked infrared flares (IR) at distances of $\sim 10$ gravitational radii ($r_g$). In this paper, we study a model for the flares based on 3D general relativistic…

High Energy Astrophysical Phenomena · Physics 2021-02-03 O. Porth , Y. Mizuno , Z. Younsi , C. M. Fromm

Sagittarius A* exhibits frequent flaring activity across the electromagnetic spectrum. Signatures of an orbiting hot spot have been identified in the polarized millimeter wavelength light curves observed with ALMA in 2017 immediately after…

High Energy Astrophysical Phenomena · Physics 2024-03-29 A. I. Yfantis , M. A. Mościbrodzka , M. Wielgus , J. T. Vos , A. Jimenez-Rosales

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 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…

‹ Prev 1 2 3 10 Next ›