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相关论文: Long-Term Radio Modulation in Sagittarius A* from …

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The mm to sub-mm spectrum of Sgr A* at the Galactic center, as well as its polarization characteristics, are consistent with the inner 10 Schwarzschild radii of a tight Keplerian emitting region of hot, magnetized, orbiting gas. This plasma…

天体物理学 · 物理学 2009-11-07 Siming Liu , Fulvio Melia

The linearly polarized millimeter and sub-millimeter emission in Sagittarius A* is produced within 10 Schwarzschild radii of the supermassive black hole at the Galactic Center and may originate from a hot magnetized accretion disk, where…

天体物理学 · 物理学 2009-11-13 Siming Liu , Lei Qian , Xue-Bing Wu , Christopher L. Fryer , Hui Li

We report on 85-101 GHz light curves of the Galactic Center supermassive black hole, Sagittarius A* (Sgr A*), observed in April 2017 with the Atacama Large Millimeter/submillimeter Array (ALMA). This study of high-cadence full-Stokes data…

The radio source Sagittarius A* (Sgr A*) is believed to be a hot, inhomogeneous, magnetized plasma flowing near the event horizon of the 3 million solar mass black hole at the galactic center. At a distance of 8000 parsecs the black hole…

天体物理学 · 物理学 2008-11-26 Scott C. Noble , Po Kin Leung , Charles F. Gammie , Laura G. Book

We compile and analyse long term (~10 year) submillimetre (1.3, 0.87, 0.43 mm, submm) wavelength light curves of the Galactic centre black hole, Sagittarius A*. The 0.87 and 0.43 mm data are taken from the literature, while the majority of…

The polarized mm/sub-mm radiation from Sgr A* is apparently produced by a Keplerian structure whose peak emission occurs within several Schwarzschild radii (r_S=2GM/c^2) of the black hole. The Chandra X-ray counterpart, if confirmed, is…

天体物理学 · 物理学 2009-11-06 Fulvio Melia , Benjamin C. Bromley , Siming Liu , Christopher , K. Walker

The supermassive black hole at the Galactic center, Sagittarius A*, has experienced periods of higher activity in the past. The reflection of these past outbursts is observed in the molecular material surrounding the black hole but…

高能天体物理现象 · 物理学 2014-10-21 Maïca Clavel , R. Terrier , A. Goldwurm , M. R. Morris , G. Ponti , S. Soldi , G. Trap

The nature of the emission region around Sagittarius A* (Sgr A*), the supermassive black hole at the Galactic Center, remains under debate. A prediction of jet models is that a frequency-dependent shift in the position of the radio core…

高能天体物理现象 · 物理学 2026-02-11 R. Fraga-Encinas , M. Moscibrodzka , H. Falcke

We report on the submillimeter properties of Sagittarius A* derived from observations with the Submillimeter Array and its polarimeter. We find that the spectrum of Sgr A* between 230 and 690 GHz is slightly decreasing when measured…

天体物理学 · 物理学 2009-11-11 Daniel P. Marrone , James M. Moran , Jun-Hui Zhao , Ramprasad Rao

Based on Bremer et al. (2011) and Eckart et al. (2012) we report on simultaneous observations and modeling of the millimeter, near-infrared, and X-ray flare emission of the source Sagittarius A* (SgrA*) associated with the super-massive…

We report the discovery of variability in the linear polarization from the Galactic Center black hole source, Sagittarius A*. New polarimetry obtained with the Berkeley-Illinois-Maryland Association array at a wavelength of 1.3 mm shows a…

天体物理学 · 物理学 2009-11-10 Geoffrey C. Bower , Heino Falcke , Melvyn C. H. Wright , Donald C. Backer

Sagittarius A* (Sgr A*) is the variable radio, near-infrared (NIR), and X-ray source associated with accretion onto the Galactic center black hole. We have analyzed a comprehensive submillimeter (including new observations simultaneous with…

Pulsar timing measurements can be used to detect gravitational radiation from massive black hole binaries. The ~106d quasi-periodic flux variations in Sagittarius A* at radio wavelengths reported by Zhao, Bower, & Goss (2001) may be due to…

天体物理学 · 物理学 2009-11-06 Andrea N. Lommen , Donald C. Backer

Sagittarius A* (Sgr A*) is the variable radio, near-infrared (NIR), and X-ray source associated with accretion onto the Galactic center black hole. We present an analysis of the most comprehensive NIR variability dataset of Sgr A* to date:…

Sagittarius A* is a compact radio source at the Galactic center, powered by accretion of fully ionized plasmas into a supermassive black hole. However, the radio emission cannot be produced through the thermal synchrotron process by a…

高能天体物理现象 · 物理学 2009-04-02 Kyle W. Martin , Siming Liu , Chris Fragile , Cong Yu , Chris L. Fryer

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…

We continue our previous work, Chan et al. 2024, to investigate how variations in the electron temperature prescription parameter, $R_{\rm Low}$, influence the $3$-hour variability at $230$\,GHz, $M_{\Delta T}$, in magnetic-arrested disk…

高能天体物理现象 · 物理学 2025-04-23 Ho-Sang Chan , Chi-kwan Chan

We analyzed 77 epochs of Atacama Large Millimeter/submillimeter Array (ALMA) archival data to investigate flux variability in Sagittarius A$^*$ (Sgr A$^*$), the supermassive black hole at the Galactic Center. Among these, we identified a…

高能天体物理现象 · 物理学 2025-11-05 Kazuki Yanagisawa , Tomoharu Oka , Ryo Ariyama , Kazuki Yanagihara , Yuhei iwata , Mikiya M. Takahashi

Sagittarius A* is the source of near infrared, X-ray, radio, and (sub)millimeter emission associated with the supermassive black hole at the Galactic Center. In the submillimeter regime, Sgr A* exhibits time-variable linear polarization on…

星系天体物理 · 物理学 2014-11-20 Vincent L. Fish , Sheperd S. Doeleman , Avery E. Broderick , Abraham Loeb , Alan E. E. Rogers

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…

天体物理学 · 物理学 2009-11-11 A. Eckart , R. Schoedel , L. Meyer , S. Trippe , T. Ott , R. Genzel