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Related papers: The Post-Pericenter Evolution of the Galactic Cent…

200 papers

Sagittarius B2 (Sgr B2) is one of the most massive and luminous star-forming regions in the Galaxy and shows chemical and physical conditions similar to those in distant extragalactic starbursts. We present large-scale far-IR/submm…

The compact radio source Sgr A* is coincident with a 4 million solar mass black hole at the dynamical center of the Galaxy and is surrounded by dense orbiting ionized and molecular gas. We present high resolution radio continuum images of…

High Energy Astrophysical Phenomena · Physics 2015-06-11 F. Yusef-Zadeh , R. Arendt , H. Bushouse , W. Cotton , D. Haggard , M. W. Pound , D. A. Roberts , M. Royster , M. Wardle

We explore the possibility that the G2 gas cloud falling in towards \sgra is the mass loss envelope of a young TTauri star. As the star plunges to smaller radius at 1000 to 6000 \kms, a strong bow shock forms where the stellar wind is…

High Energy Astrophysical Phenomena · Physics 2015-06-15 Nick Scoville , Andi Burkert

We have collected in 2004 adaptive optics corrected L' images of the Galactic Center region with NAOS-CONICA at VLT. A strong variability was observed as well as a correlation between the photocenter positions and fluxes of the L'-band…

We analyze deep near-IR adaptive optics imaging as well as new proper motion data of the nuclear star cluster of the Milky Way. The surface density distribution of faint stars peaks within 0.2" of the black hole candidate SgrA*. The radial…

A possibility of time-delayed radio brightenings of Sgr A* triggered by the pericenter passage of the G2 cloud is studied by carrying out global three-dimensional magnetohydrodynamic simulations taking into account the radiative cooling of…

High Energy Astrophysical Phenomena · Physics 2017-04-11 Tomohisa Kawashima , Yosuke Matsumoto , Ryoji Matsumoto

We present new observations of the [Ne II] emission from the ionized gas in Sgr A West with improved resolution and sensitivity. About half of the emission comes from gas with kinematics indicating it is orbiting in a plane tipped about…

Astrophysics of Galaxies · Physics 2015-06-05 Wesley T. Irons , John H. Lacy , Matthew J. Richter

We perform detailed magnetohydrodynamic simulations of the gas cloud G2 interacting with the accretion flow around the Galactic Center black hole Sgr A*. We take as our initial conditions a steady-state, converged solution of the accretion…

High Energy Astrophysical Phenomena · Physics 2015-06-15 A. Sadowski , R. Narayan , L. Sironi , F. Ozel

We report measurements with the Very Long Baseline Array of the proper motion of Sgr A* relative to two extragalactic radio sources spanning 18 years. The apparent motion of Sgr A* is -6.411 +/- 0.008 mas/yr along the Galactic plane and…

Astrophysics of Galaxies · Physics 2020-04-01 M. J. Reid , A. Brunthaler

We suggest that the energy source of the observed diffuse gamma-ray emission from the direction of the Galactic center is the Galactic black hole Sgr A*, which becomes active when a star is captured at a rate of $\sim 10^{-5} $ yr^{-1}.…

Astrophysics · Physics 2009-11-13 K. S. Cheng , D. O. Chernyshov , V. A. Dogiel

We present 44 and 226 GHz observations of the Galactic center within 20$"$ of Sgr A*. Millimeter continuum emission at 226 GHz is detected from eight stars that have previously been identified at near-IR and radio wavelengths. We also…

High Energy Astrophysical Phenomena · Physics 2017-08-02 F. Yusef-Zadeh , R. Schödel , M. Wardle , H. Bushouse , W. Cotton , M. J. Royster , D. Kunneriath , D. A. Roberts , E. Gallego-Cano

The mini-spiral is a feature of the interstellar medium in the central ~2 pc of the Galactic center. It is composed of several streamers of dust and ionised and atomic gas with temperatures between a few 100 K to 10^4 K. There is evidence…

In recent years, there has been increasing recognition of the potential of the galactic center as a probe of general relativity in the strong field. There is almost certainly a black hole at Sgr A* in the galactic center, and this would…

General Relativity and Quantum Cosmology · Physics 2011-05-24 Amitai Y. Bin-Nun

We re-examine the nature of NGC2024-IRS2 in light of the recent discovery of the late O-type star, IRS2b, located 5 arcsec from IRS2. Using L-band spectroscopy, we set a lower limit of Av = 27.0 mag on the visual extinction towards IRS2.…

Empirically determining the averaged variations of the orbital parameters of the stars orbiting the Supermassive Black Hole (SBH) hosted by the Galactic Centre (GC) in Sgr A* is, in principle, a valuable tool to put on the test the General…

General Relativity and Quantum Cosmology · Physics 2017-10-06 Lorenzo Iorio

The ionized core in the Sgr B2 Main star-forming region was imaged using the Submillimeter Array archival data observed for the H26$\alpha$ line and continuum emission at 0.86 millimeter with an angular resolution 0.3\arcsec. Eight…

Solar and Stellar Astrophysics · Physics 2015-05-30 Jun-Hui Zhao , M. C. H. Wright

Sub milli-arcsecond astrometry and imaging of the black hole Sgr A* at the Galactic centre may become possible in the near future at infrared and sub-millimetre wavelengths. Motivated by observations of short-term infrared and X-ray…

Astrophysics · Physics 2009-11-13 Avery E. Broderick , Abraham Loeb

We have investigated the linear X-ray filament, G359.944-0.052, previously identified as a likely X-ray counterpart of a parsec-scale jet from the Galactic Center super-massive black hole (SMBH), Sagittarius A* (Sgr A*), using a total of…

High Energy Astrophysical Phenomena · Physics 2019-04-17 Zhenlin Zhu , Zhiyuan Li , Mark R. Morris , Shuo Zhang , Siming Liu

We report the association of the recently discovered hard X-ray source IGR J17475-2822 with the giant molecular cloud Sgr B2 in the Galactic Center region. The broad band (3-200 keV) spectrum of the source constructed from data of different…

We report on the first far-IR detection of H2D+, using the Infrared Space Observatory, in the line of sight toward Sgr B2 in the galactic center. The transition at 126.853 um connecting the ground level of o-H2D+, 1_1,1 with the the 2_1,2…

Astrophysics · Physics 2009-11-13 J. Cernicharo , E. Polehampton , J. R. Goicoechea