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相关论文: HI Kinematics, Mass Distribution, and Star Formati…

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We present Spitzer imaging of the metal-deficient (Z ~30% Z_sun) Local Group dwarf galaxy NGC 6822. On spatial scales of ~130 pc, we study the nature of IR, H alpha, HI, and radio continuum emission. Nebular emission strength correlates…

Star counts, obtained from a 2 x 2 degree area centered on NGC 6822 have revealed an optical image of this galaxy composed of two components: in addition to the well-known HI disk with its young stellar component, there is a spheroidal…

天体物理学 · 物理学 2016-08-30 Serge Demers , Paolo Battinelli , William E. Kunkel

The star formation histories of four fields within the Local Group dwarf irregular galaxy NGC 6822 are presented. Each of the fields was imaged by the WFPC2 aboard the {\it Hubble Space Telescope} and were used to obtain $VI$…

天体物理学 · 物理学 2009-11-07 Ted K. Wyder

We present a panoramic survey of the isolated Local Group dwarf irregular galaxy NGC 6822. Our photometry reaches $\sim2-3$ magnitudes deeper than most previous studies and spans the widest area around the dwarf compared to any prior work.…

星系天体物理 · 物理学 2021-09-22 Shumeng Zhang , Dougal Mackey , Gary Da Costa

We present high resolution rotation curves of the local group dwarf irregular galaxy NGC 6822 obtained with the Australia Telescope Compact Array. Our best curves have an angular resolution of 8'' or 20 pc and contain some 250 independent…

天体物理学 · 物理学 2009-09-28 David Weldrake , Erwin de Blok , Fabian Walter

We map the Hi distribution of galaxies in a $\sim 1.5^\circ \times 2.5^\circ$ region located at the virial radius south of the Virgo cluster using the KAT$-$7 and the WSRT interferometers. Because of the different beam sizes of the two…

星系天体物理 · 物理学 2016-09-14 Amidou Sorgho , Kelley M. Hess , Claude Carignan , Tom A. Oosterloo

We present a detailed photometric study of the dwarf irregular galaxy NGC 6822 aimed at investigating the properties of its stellar populations and, in particular, the presence of stellar radial gradients. Our goal is to analyse the stellar…

星系天体物理 · 物理学 2014-11-26 F. Fusco , R. Buonanno , S. L. Hidalgo , A. Aparicio , A. Pietrinferni , G. Bono , M. Monelli , S. Cassisi

Atomic hydrogen (HI) dominates the mass of the cold interstellar medium, undergoing thermal condensation to form molecular gas and fuel star formation. Kinematically colder HI components, identified via kinematic decomposition of HI 21 cm…

We present a detailed analysis of the chemistry and kinematics of red giants in the dwarf irregular galaxy NGC 6822. Spectroscopy at 8500 Angstroms was acquired for 72 red giant stars across two fields using FORS2 at the VLT. Line of sight…

星系天体物理 · 物理学 2016-02-08 Jesse Swan , Andrew A. Cole , Eline Tolstoy , Mike J. Irwin

We use the IRAM HERACLES survey to study CO emission from 33 nearby spiral galaxies down to very low intensities. Using atomic hydrogen (HI) data, mostly from THINGS, we predict the local mean CO velocity from the mean HI velocity. By…

We present the ALMA survey of CO(2-1) emission from the 1/5 solar metallicity, Local Group dwarf galaxy NGC 6822. We achieve high (0.9 arcsec ~ 2 pc) spatial resolution while covering large area: four 250 pc x 250 pc regions that encompass…

Do molecular clouds collapse to form stars at the same rate in all environments? In large spiral galaxies, the rate of transformation of H2 into stars (hereafter SFE) varies little. However, the SFE in distant objects (z~1) is much higher…

宇宙学与河外天体物理 · 物理学 2010-04-06 P. Gratier , J. Braine , N. J. Rodriguez-Fernandez , F. P. Israel , K. F. Schuster , N. Brouillet , E. Gardan

The CO-to-H$_2$ conversion factor ($\alpha_\rm{CO}$) is central to measuring the amount and properties of molecular gas. It is known to vary with environmental conditions, and previous studies have revealed lower $\alpha_\rm{CO}$ in the…

We present a spectroscopic study of the four extended star clusters (ESCs) in NGC 6822 based on the data obtained with Gemini Multi-Object Spectrograph (GMOS) on the Gemini-South 8.1m telescope. Their radial velocities derived from the…

We present a comprehensive study of the star cluster population and the hierarchical structure in the clustering of blue stars with ages <~ 500 Myr in the Local Group dwarf irregular galaxy NGC 6822. Our observational material comprises the…

星系天体物理 · 物理学 2015-05-20 Dimitrios A. Gouliermis , Stefan Schmeja , Ralf S. Klessen , W. J. G. de Blok , Fabian Walter

We present line-of-sight stellar velocity distributions of elliptical galaxy NGC 821 obtained to approximately 100 arcsec (over 2 effective radii) with long-slit spectroscopy from the Hobby-Eberly Telescope. Our measured stellar…

天体物理学 · 物理学 2011-01-20 Amy Forestell , Karl Gebhardt

Halpha and UBV photometry of NGC 6822 are used to study the distribution of OB stars and HII regions in the galaxy and to determine whether individual regions of the galaxy are in a state of ionization balance. Four distinct components of…

天体物理学 · 物理学 2009-10-28 K. Patel , C. D. Wilson

We present a comprehensive analysis of the globular cluster (GC) system of the Local Group dwarf irregular galaxy NGC 6822. Our study is based on homogeneous optical and near-IR photometry, as well as long-slit spectroscopic observations…

Crucial to a quantitative understanding of galaxy evolution are the properties of the inter-stellar medium that regulate galactic-scale star formation activity. We present here the results of a suite of star formation models applied to the…

宇宙学与河外天体物理 · 物理学 2015-05-30 E C Elson , W J G de Blok , R C Kraan-Korteweg