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Related papers: K-shell Emission of Neutral Iron Line from Sgr B2 …

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(Abridged) The inner couple hundred pcs of our Galaxy is characterized by significant amount of synchrotron-emitting gas, which appears to co-exist with a large reservoir of molecular gas. The spatial correlation between fluorescent Fe…

Astrophysics · Physics 2008-11-26 F. Yusef-Zadeh , M. Muno , M. Wardle , D. C. Lis

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

The relatively rapid spatial and temporal variability of the X-ray radiation from some molecular clouds near the Galactic center shows that this emission component is due to the reflection of X-rays generated by a source that was luminous…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Maïca Clavel , R. Terrier , A. Goldwurm , M. R. Morris , G. Ponti , S. Soldi , G. Trap

We present the result of a study of the X-ray emission from the Galactic Centre (GC) Molecular Clouds (MC) within 15 arcmin from Sgr A*. We use XMM-Newton data (about 1.2 Ms of observation time) spanning about 8 years. The MC spectra show…

High Energy Astrophysical Phenomena · Physics 2015-05-18 Gabriele Ponti , Regis Terrier , Andrea Goldwurm , Guillaume Belanger , Guillaume Trap

The fluorescent X-ray emission from neutral iron in the molecular clouds (Sgr B) indicates that the clouds are being irradiated by an external X-ray source. The source is probably associated with the Galactic central black hole (Sgr A*),…

High Energy Astrophysical Phenomena · Physics 2012-07-11 Yun-Wei Yu , K. S. Cheng , D. O. Chernyshov , V. A. Dogiel

Molecular cloud Sgr B2 is a natural Compton mirror in the Central Molecular Zone. An observed fading of the Sgr B2 X-ray emission in continuum and Fe K$\alpha$ 6.4 keV line indicates, as believed, a past X-ray flare activity of the…

High Energy Astrophysical Phenomena · Physics 2021-11-24 Ekaterina Kuznetsova , Roman Krivonos , Alexander Lutovinov , Maïca Clavel

We present highly sensitive measurements taken with MeerKAT at 1280 MHz as well as archival GBT, MWA and VLA images at 333, 88 and 74 MHz. We report the detection of synchrotron radio emission from the infrared dark cloud (IRDC) associated…

High Energy Astrophysical Phenomena · Physics 2023-11-01 F. Yusef-Zadeh , M. Wardle , R. Arendt , J. W. Hewitt , Y. Hu , A. Lazarian , N. Kassim , S. Hyman , I. Heywood

We present the result of a study of the X-ray emission from the Galactic Centre Molecular Clouds (MC), within 15 arcmin from Sgr A*. We use XMM-Newton data spanning about 8 years. We observe an apparent super-luminal motion of a light front…

High Energy Astrophysical Phenomena · Physics 2010-04-12 Gabriele Ponti , Regis Terrier , Andrea Goldwurm , Guillaume Belanger , Guillaume Trap

The recent discovery of the G2 cloud of dense, ionized gas on a trajectory toward Sgr A*, the black hole at the dynamical center of the Galaxy, offers a unique opportunity to observe an accretion event onto a massive black hole as well as…

High Energy Astrophysical Phenomena · Physics 2015-06-15 F. Yusef-Zadeh , M. Wardle

We present imaging and spatially resolved spectral analyses of eight Chandra data taken for the Circinus galaxy in $\approx$ 22 years to reveal neutral iron-K$\alpha$ emission on a circumnuclear scale ($\sim$ 10--100 pc) and search for time…

Astrophysics of Galaxies · Physics 2026-01-22 Aiko Miyamoto , Taiki Kawamuro , Hirokazu Odaka , Takuma Izumi , Hironori Matsumoto

Information about the X-ray luminosity of the supermassive black hole located at the Galactic center (GC), Sgr A*, and its temporal variations in the past is imprinted in the scattered emission observed today in the direction towards giant…

Astrophysics · Physics 2009-11-07 Conrad K. Cramphorn , Rashid A. Sunyaev

We investigate the origin of the diffuse 6.4 keV line emission recently detected by Suzaku and the source of H_2ionization in the diffuse molecular gas of the Galactic Center (GC) region. We show that Fe atoms and H_2 molecules in the…

High Energy Astrophysical Phenomena · Physics 2015-06-16 V. A. Dogiel , D. O. Chernyshov , V. Tatischeff , K. -S. Cheng , R. Terrier

The origin and the profile of the iron K-alpha line from active galactic nuclei is being studied. The model with a quasi-spherical distribution of clouds around a compact galactic nucleus is explored in which the intrinsic spectral feature…

Astrophysics · Physics 2011-05-10 V. Karas , B. Czerny , Z. Abrassart , M. Abramowicz

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…

High Energy Astrophysical Phenomena · Physics 2014-10-21 Maïca Clavel , R. Terrier , A. Goldwurm , M. R. Morris , G. Ponti , S. Soldi , G. Trap

We report the results of X-ray (2-10 keV) observations of the giant molecular clouds SgrB, SgrC and SgrD in the Galactic Center region, together with the discovery of the point-like source SAXJ1748.2-2808. The data have been obtained with…

Astrophysics · Physics 2009-11-06 L. Sidoli , S. Mereghetti , A. Treves , A. N. Parmar , R. Turolla , F. Favata

We report the diffuse X-ray emissions from the Sgr A and B regions observed with Suzaku. From the Sgr A region, we found many K-shell transition lines of iron and nickel. The brightest are K alpha lines from FeI, FeXXV and FeXXVI at 6.4…

Astrophysics · Physics 2008-11-26 Katsuji Koyama , Yoshiaki Hyodo , Tatsuya Inui

A dense ionized cloud of gas has been recently discovered to be moving directly toward the supermassive black hole, Sgr A*, at the Galactic Center. In June 2013, at the pericenter of its highly eccentric orbit, the cloud will be…

Astrophysics of Galaxies · Physics 2015-06-05 Ramesh Narayan , Feryal Ozel , Lorenzo Sironi

The K-shell emission line of neutral irons from the Galactic center (GC) region is one of the key for the structure and activity of the GC. The origin is still open question, but possibly due either to X-ray radiation or to electron…

High Energy Astrophysical Phenomena · Physics 2015-05-18 Masayoshi Nobukawa , Katsuji Koyama , Takeshi Go Tsuru , Syukyo G Ryu , Vincent Tatischeff

We present 168 arcmin^2 spectral images of the Sgr B2 complex taken with Herschel/SPIRE-FTS. We detect ubiquitous emission from CO (up to J=12-11), H2O, [CI]492, 809 GHz, and [NII] 205 um lines. We also present maps of the SiO, N2H+, HCN,…

Astrophysics of Galaxies · Physics 2021-05-12 M. G. Santa-Maria , J. R. Goicoechea , M. Etxaluze , J. Cernicharo , S. Cuadrado

In order to elucidate origin of the Galactic Ridge X-ray Emission, we analyzed Suzaku data taken at various regions along the Galactic plane and studied their Fe-K emission line features. Suzaku resolved the Fe line complex into three…