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

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We present K-band $\lambda/\Delta\lambda$ ~ 2600 spectroscopy of five stars (K ~ 14 - 16 mag) within 0.''5 of Sgr A*, the radio source associated with the compact massive object suspected to be a 2.6 x 10$^{6}$ \msun black hole at the…

Astrophysics · Physics 2009-11-07 S. Gezari , A. M. Ghez , E. E. Becklin , J. Larkin , I. S. McLean , M. Morris

We report progress on measuring the position of Sgr A* on infrared images, placing limits on the motion of the central star cluster relative to Sgr A*, and measuring the proper motionof Sgr A* itself. The position of Sgr A* has been…

Astrophysics · Physics 2009-11-07 M. J. Reid , K. M. Menten , R. Genzel , T. Ott , R. Schoedel , A. Eckart , A. Brunthaler

Over a two year period (1995-1997), we have conducted a diffraction-limited imaging study at 2.2 microns of the inner 6"x6" of the Galaxy's central stellar cluster using the Keck 10-m telescope. The K band images obtained reveal a large…

Astrophysics · Physics 2009-10-30 A. M. Ghez , B. L. Klein , M. Morris , E. E. Becklin

The Galactic Center was observed at 8.6 mum in order to detect a mid-infrared (MIR) counterpart of Sgr A*, parallel to NIR observations. The goal was to set constraints on possible emission mechanisms.Imaging data were acquired with the…

Astrophysics · Physics 2007-05-23 R. Schoedel , A. Eckart , K. Muzic , L. Meyer , T. Viehmann , G. C. Bower

We present results of our Chandra observation with the ACIS-I instrument centered on the position of Sagittarius A* (Sgr A*), the compact nonthermal radio source associated with the massive black hole (MBH) at the dynamical center of the…

L'-band (lambda=3.8 microns) and M'-band (lambda=4.8 microns) observations of the Galactic Center region, performed in 2003 at VLT (ESO) with the adaptive optics imager NACO, have lead to the detection of an infrared counterpart of the…

Astrophysics · Physics 2016-08-16 Y. Clénet , D. Rouan , D. Gratadour , F. Lacombe , E. Gendron , R. Genzel , T. Ott , R. Schödel , P. Léna

We analyze the gas and dust emission in the immediate vicinity of the supermassive black hole Sgr~A* at the Galactic center (GC) with the ESO VLT (Paranal/Chile) instruments SINFONI and VISIR. The SINFONI H+K data cubes show several…

Astrophysics of Galaxies · Physics 2020-07-08 Florian Peißker , Andreas Eckart , Nadeen B. Sabha , Michal Zajaček , Harshitha Bhat

Menten, Reid, Eckart and Genzel (1997) accurately determined the position of Sgr A* on an infrared image, by aligning the infrared image with positions measured for SiO masers, associated with infrared-bright evolved stars, at radio…

Astrophysics · Physics 2009-11-07 M. J. Reid , K. M. Menten , R. Genzel , T. Ott , R. Schoedel , A. Eckart

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

Until now the known sources in the Galactic center with sufficiently smooth spectra and of sufficient brightness to be suitable for high resolution infrared absorption spectroscopy of interstellar gas occupied a narrow range of longitudes,…

Astrophysics of Galaxies · Physics 2015-05-14 T. R. Geballe , T. Oka

ALMA observations of the Galactic center with spatial resolution $2.61"\times0.97"$ resulted in the detection of 11 SiO (5-4) clumps of molecular gas within 0.6pc (15$"$) of Sgr A*, interior to the 2-pc circumnuclear molecular ring. The…

Astrophysics of Galaxies · Physics 2015-06-15 F. Yusef-Zadeh , M. Royster , M. Wardle , R. Arendt , H. Bushouse , D. C. Lis , M. W. Pound , D. A. Roberts , B. Whitney , A. Wootten

This paper presents and examines new near-infrared integral field observations of the three so-called 'embedded star clusters' located in the nuclear region of NGC1365. Adaptive-optics- corrected K-band data cubes were obtained with the…

Astrophysics of Galaxies · Physics 2015-06-05 Emmanuel Galliano , Markus Kissler-Patig , Danielle Alloin , Eduardo Telles

We have obtained the first detection of spectral absorption lines in one of the high-velocity stars in the vicinity of the Galaxy's central supermassive black hole. Both Brgamma (2.1661 micron) and He I (2.1126 micron) are seen in…

We present proper motions for $>$40 stars at projected distances $\leq1.2''$ from Sagittarius A* (Sgr A*). We find evidence on a $\geq2\sigma$ level for radial anisotropy of the cluster of stars within $1''$ of Sgr A*. We find no evidence…

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

The central region of the Galaxy has been observed at 580, 620 and 1010 MHz with the Giant Metrewave Radio Telescope (GMRT). We detect emission from Sgr-A*, the compact object at the dynamical centre of the Galaxy, and estimate its flux…

Astrophysics · Physics 2009-11-10 Subhashis Roy , A. Pramesh Rao

We report 75 milli-arcsec resolution, near-IR imaging spectroscopy within the central 30 light days of the Galactic Center [...]. To a limiting magnitude of K~16, 9 of 10 stars in the central 0.4 arcsec, and 13 of 17 stars out to 0.7 arcsec…

(Abridged) We present the first Laser Guide Star Adaptive Optics (LGS-AO) observations of the Galactic center. LGS-AO has dramatically improved the quality, robustness, and versatility with which high angular resolution infrared images of…

We have performed near-infrared monitoring observations of Sgr A*, the Galactic center radio source associated with a supermassive black hole, with the near-infrared camera CIAO and the 36-element adaptive optics system on the Subaru…

We present high spatial resolution, medium spectral resolution near-infrared (NIR) H- and K-band long-slit spectroscopy for a sample of 29 nearby (z < 0.01) inactive spiral galaxies, to study the composition of their NIR stellar…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 J. K. Kotilainen , T. Hyvonen , J. Reunanen , V. D. Ivanov

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…

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