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Related papers: The Stellar Content Near the Galactic Center

200 papers

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…

We present first results from a submillimetre continuum survey of the Galactic Centre `Central Molecular Zone' (CMZ), made with SCUBA on the James Clerk Maxwell Telescope. SCUBA's scan-map mode has allowed us to make extremely wide-field…

Known bright S stars, recognized as such by their enhanced s-process abundances and C/O ratio, are typically members of the asymptotic giant branch (AGB) or the red giant branch (RGB). Few modern digital spectra for these objects have been…

Solar and Stellar Astrophysics · Physics 2015-05-28 Elizabeth Otto , Paul J Green , Richard O. Gray

Observations of the innermost parsec surrounding Sgr A$^*$ ---the supermassive black hole in the center of our Galaxy--- have revealed a diversity of structures whose existence and characteristics apparently defy the fundamental principles…

Astrophysics of Galaxies · Physics 2015-06-23 Xian Chen , Pau Amaro-Seoane

Extensive photometric studies of the globular clusters located towards the center of the Milky Way have been historically neglected. The presence of patchy differential reddening in front of these clusters has proven to be a significant…

During the period Aug.23-Sept.24 2003, the INTEGRAL observatory performed an ultra deep survey of the Galactic Center region with a record sensitivity at energies higher than 20 keV. We have analized images of the Galactic Center region…

We present a catalogue of 107 point-like X-ray sources derived from a systematic analysis of all the ROSAT PSPC observations of the galactic center region performed in 1992-1993. Besides SgrA*, the massive black hole at the galactic center,…

Astrophysics · Physics 2009-11-06 L. Sidoli , T. Belloni , S. Mereghetti

We are performing a survey of the Galactic Center region with the BeppoSAX satellite. Several known point sources are visible (including one at the position of SgrA*), as well as newly discovered sources and diffuse emission. Here we report…

Astrophysics · Physics 2007-05-23 L. Sidoli , S. Mereghetti

We present a near infrared study of the stellar content of 35 H\,{\sc{ii}} regions in the Galactic plane. In this work, we have used the near infrared domain $J-$, $H-$ and $K_{s}-$ band color images to visually inspect the sample. Also,…

Solar and Stellar Astrophysics · Physics 2015-05-20 A. P. Moisés , A. Damineli , E. Figuerêdo , R. D. Blum , P. S. Conti , C. L. Barbosa

We consider the absorption and scattering of X-rays observed from the Galactic center. One objective is to characterize the intrinsic X-ray emission from the central black hole, SgrA*, in its quiescent and flaring states. We correct the…

Astrophysics · Physics 2009-11-10 Jonathan C. Tan , B. T. Draine

Recent results from the HESS gamma ray telescope have shown the presence of both a diffuse, extended, flux of gamma rays above ~0.4 TeV and discrete sources in and near the Galactic Centre. Here, we put forward a possible explanation in…

Astrophysics · Physics 2009-06-23 A. D. Erlykin , A. W. Wolfendale

We report new observations of multiple transitions of the CS molecular lines in the SgrA region of the Galactic center, at an angular resolution of 40" (=1.5 pc). The objective of this paper is to study the polar arc, which is a molecular…

Astrophysics of Galaxies · Physics 2015-10-13 Pei-Ying Hsieh , Paul T. P. Ho , Chorng-Yuan Hwang

We report observations and analysis of infrared spectra of H3+ and CO lines in the Galactic center, within a few parsecs of the central black hole, Sgr A*. We find a cosmic ray ionization rate typically an order of magnitude higher than…

Astrophysics of Galaxies · Physics 2015-06-16 M. Goto , Nick Indriolo , T. R. Geballe , T. Usuda

We briefly review the prominent thermal and nonthermal sources near the Galactic center. These sources include the young stellar clusters, the Sgr B complex as well as the large-scale nonthermal filaments and lobes. Some of the recent radio…

Astrophysics · Physics 2007-05-23 F. Yusef-Zadeh , W. Cotton , J. Hewitt , C. Law , R. Maddalena , D. A. Roberts

The absolute position of the compact radio source at the dynamical center of the Galaxy, Sgr A$^*$, was known only to an accuracy of $0.2''$ in spite of its accurate location with respect to near-IR stellar sources to within 30…

Astrophysics · Physics 2009-10-31 F. Yusef-Zadeh , D. Choate , W. Cotton

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…

We present the first event-horizon-scale images and spatiotemporal analysis of Sgr A* taken with the Event Horizon Telescope in 2017 April at a wavelength of 1.3 mm. Imaging of Sgr A* has been conducted through surveys over a wide range of…

High Energy Astrophysical Phenomena · Physics 2023-11-17 The Event Horizon Telescope Collaboration

Context: The stellar populations in the central region of the Galaxy are poorly known because of the high visual extinction and very great source density in this direction. Aims: To use recent infrared surveys for studying the dusty stellar…

Astrophysics · Physics 2012-07-07 F. Schuller , A. Omont , I. S. Glass , M. Schultheis , M. P. Egan , S. D. Price

We describe the potential of high resolution imaging spectroscopy with the SXS on ASTRO-H to advance our understanding of the interstellar- and circumgalactic media of our own Galaxy, and other galaxies. Topics to be addressed range from…

X-ray reflection off dense molecular clouds in the Galactic Centre region has established itself as a powerful probe for the past activity record of the supermassive black hole Sgr A* on a timescale of a few hundred years. Detailed studies…

High Energy Astrophysical Phenomena · Physics 2021-12-22 Ildar Khabibullin , Eugene Churazov , Rashid Sunyaev