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Related papers: The Sgr A* Stellar Cluster: New NIR Imaging and Sp…

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With 10 years of high-resolution imaging data now available on the stellar cluster in the Galactic Center, we analyze the dynamics of the stars at projected distances $\leq1.2''$ from the central black hole candidate Sagittarius A* (Sgr…

Astrophysics · Physics 2009-11-07 R. Schoedel , R. Genzel , T. Ott , A. Eckart

Very Large Array observations of the Galactic Center at 7 mm have produced an image of the 30 arcseconds surrounding Sgr A* with a resolution of 82x42 milliarcseconds (mas). A comparison with IR images taken simultaneously with the Very…

Astrophysics of Galaxies · Physics 2015-06-22 F. Yusef-Zadeh , D. A. Roberts , H. Bushouse , M. Wardle , W. Cotton , M. Royster , G. van Moorsel

We present 1"-resolution ALMA observations of the circumnuclear disk (CND) and the environment around SgrA*. The images unveil the presence of small spatial scale CO (J=3-2) molecular "cloudlets" within the central pc of the Milky Way,…

Near-infrared observations of stellar orbits at the Galactic Center provide conclusive evidence for a massive black hole associated with the compact radio source Sgr A*. The astrometric reference frame for these observations is tied to a…

Astrophysics of Galaxies · Physics 2015-09-08 P. M. Plewa , S. Gillessen , F. Eisenhauer , T. Ott , O. Pfuhl , E. George , J. Dexter , M. Habibi , R. Genzel , M. J. Reid , K. M. Menten

This work presents the results from extending the long-term monitoring program of stellar motions within the Galactic Center to include stars with separations of 2 - 7 arcseconds from the compact radio source, Sgr A*. In comparison to the…

At the center of the Milky Way lurks a unique compact nonthermal radio source, Sgr A*. It is thought to be powered by a 2.6 million solar mass black hole that is accreting the stellar winds from the numerous early-type stars that exist in…

Astrophysics · Physics 2007-05-23 R. F. Coker , S. Markoff

In the first two papers of this series, we determined the position of Sgr A* on infrared images, by aligning the positions of red giant stars with positions measured at radio wavelengths for their circumstellar SiO masers. In this paper, we…

Astrophysics · Physics 2011-02-11 M. J. Reid , K. M. Menten , S. Trippe , T. Ott , R. Genzel

The Ibis/Isgri imager on Integral detected for the first time a hard X-ray source, IGR J17456-2901, located within 1' of Sgr A* over the energy range 20-100 keV. Here we present the results of a detailed analysis of ~7 Ms of Integral…

Stars orbiting within 1$\arcsec$ of the supermassive black hole in the Galactic Centre, Sgr A*, are notoriously difficult to detect due to obscuration by gas and dust. We show that some stars orbiting this region may be detectable via…

Astrophysics of Galaxies · Physics 2015-10-28 Idan Ginsburg , Xiawei Wang , Abraham Loeb , Ofer Cohen

We have made angular broadening measurements in the satellite line of the OH molecule at 1612 MHz of 8 OH/IR stars located near the Galactic Center with the Very Large Array. Early observations with the Very Long Baseline Array had revealed…

Astrophysics · Physics 2009-10-22 D. A. Frail , P. J. Diamond , J. M. Cordes , H. J. Van Langevelde

We report on recent near-infrared (NIR) and X-ray observations of Sagittarius A* (Sgr A*), the electromagnetic manifestation of the ~4x10^6 solar masses super-massive black hole (SMBH) at the Galactic Center. The goal of these coordinated…

We analyze the stellar absorption features in high signal-to-noise ratio near-infrared (NIR) spectra of the nuclear region of 12 nearby galaxies, mostly spirals. The features detected in some or all of the galaxies in this sample are the…

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

The super-massive 4 million solar mass black hole (SMBH) SgrA* shows flare emission from the millimeter to the X-ray domain. The nucleus of the Milky Way has properties (stellar cluster, young stars, molecular gas and an accreting SMBH)…

We present numerical simulations of stellar wind dynamics in the central parsec of the Galactic centre, studying in particular the accretion of gas on to Sgr A*, the super-massive black hole. Unlike our previous work, here we use…

Astrophysics · Physics 2009-03-08 Jorge Cuadra , Sergei Nayakshin , Fabrice Martins

We present a catalog of 110 variable stars within ~1' of Sgr A* based on image subtraction of near-infrared (H and K) photometry. Our images were obtained over 133 nights from 2000--2002 in H-band and over 134 nights from 2001--2002 in…

Astrophysics · Physics 2007-08-06 Molly S. Peeples , K. Z. Stanek , D. L. DePoy

We are studying the extremely young cluster of M17 to investigate the birth of high-mass stars and the initial mass function. Deep JHKL imaging and K-band spectroscopy from the VLT of 201 stars toward the cluster is presented. The majority…

Astrophysics · Physics 2009-11-11 V. H. Hoffmeister , R. Chini , C. M. Scheyda , D. Nuernberger , N. Vogt , M. Nielbock

We present new proper motion measurements and simultaneous orbital solutions for three newly identified (S0-16, S0-19, and S0-20) and four previously known (S0-1, S0-2, S0-4, and S0-5) stars at the Galactic Center. This analysis pinpoints…

Astrophysics · Physics 2009-02-18 A. M. Ghez , S. Salim , S. D. Hornstein , A. Tanner , J. R. Lu , M. Morris , E. E. Becklin , G. Duchene

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

The Infrared Space Observatory Long wavelength Spectrometerhas been used to map distribution of the emission from a sample of 22 atomic, molecular and ionised lines toward the Circumnuclear Disk at the Galactic Centre. The CND disc is…

Astrophysics · Physics 2007-05-23 Glenn J. White , H. A. Smith , G. Stacey , C. Matt Bradford , S. J. Leeks , O. Sweet , J. Fischer