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Related papers: The Star Formation Threshold in NGC 6822

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We present high sensitivity HI observations of NGC 6822, obtained with the Karoo Array Telescope (KAT-7). We study the kinematics, the mass distribution, and the star formation thresholds. The KAT-7 short baselines and low system…

Astrophysics of Galaxies · Physics 2017-11-08 Brenda Namumba , Claude Carignan , Sean Passmoor , Erwin de Blok

NGC 6822 is an isolated dwarf irregular galaxy in the local group at a distance of 490 kpc. In this paper, we present the star formation history (SFH) within a field with a radius of 3 kpc, beyond the optical body of the galaxy (1.2 kpc).…

Astrophysics of Galaxies · Physics 2025-01-28 Fatemeh Khatamsaz , Mahdi Abdollahi , Hedieh Abdollahi , Atefeh Javadi , Jacco Th. van Loon

We present H I gas kinematics and star formation activities of NGC 6822, a dwarf galaxy located in the Local Group at a distance of ~ 490 kpc. We perform profile decomposition of line-of-sight velocity profiles of the H I data cube (42.4" x…

Astrophysics of Galaxies · Physics 2022-08-17 Hye-Jin Park , Se-Heon Oh , Jing Wang , Yun Zheng , Hong-Xin Zhang , W. J. G. de Blok

Images of five fields in the Local Group dwarf irregular galaxy NGC 6822 obtained with the {\it Hubble Space Telescope} in the F555W and F814W filters are presented. Photometry for the stars in these images was extracted using the…

Astrophysics · Physics 2009-11-07 Ted K. Wyder

Our proposed method to study the star formation histories in nearby irregulars is here applied to NGC 6822. To this purpose we have obtained accurate CCD photometry of three regions in the galaxy, reaching V$\simeq$23.5 with an accuracy of…

Astrophysics · Physics 2009-10-22 G. Marconi , M. Tosi , L. Greggio , P. Focardi

We characterize the star formation in the low-metallicity galaxy NGC 6822 over the past few hundred million years, using GALEX far-UV (FUV, 1344-1786 A) and near-UV (NUV, 1771-2831 A) imaging, and ground-based Ha imaging. From GALEX FUV…

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 $VI$…

Astrophysics · Physics 2009-11-07 Ted K. Wyder

We present wide-field optical imaging covering the entire neutral hydrogen disc of the Local Group dwarf galaxy NGC 6822. These observations reveal the presence of numerous blue, young stars at large galactocentric radii well beyond R_25.…

Astrophysics · Physics 2009-11-07 W. J. G. de Blok , F. Walter

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.…

Astrophysics of Galaxies · Physics 2021-09-22 Shumeng Zhang , Dougal Mackey , Gary Da Costa

We have previously established, from a carbon star survey, that the Local Group dwarf irregular galaxy NGC 6822 is much larger than its central bright core. Four MegaCam fields are acquired to survey a 2$^\circ\times$ 2$^\circ$ area centred…

Astrophysics · Physics 2016-08-30 P. Battinelli , S. Demers , W. E. Kunkel

Three molecular clouds have been mapped in the nearby metal-poor dwarf irregular galaxy NGC 6822 using the Owens Valley Millimeter-Wave Interferometer. Based on upper limits to the virial masses of the clouds, the CO-to-H2 conversion factor…

Astrophysics · Physics 2009-10-22 C. D. Wilson

Measuring the properties of the cold neutral medium (CNM) in low-metallicity galaxies provides insight into heating and cooling mechanisms in early Universe-like environments. We report detections of two localized atomic neutral hydrogen…

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…

Astrophysics · Physics 2016-08-30 Serge Demers , Paolo Battinelli , William E. Kunkel

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…

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…

Astrophysics of Galaxies · Physics 2015-05-20 Dimitrios A. Gouliermis , Stefan Schmeja , Ralf S. Klessen , W. J. G. de Blok , Fabian Walter

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…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-06 P. Gratier , J. Braine , N. J. Rodriguez-Fernandez , F. P. Israel , K. F. Schuster , N. Brouillet , E. Gardan

We present HST WFPC2 and STIS imaging of the low metallicity galaxy NGC 6822, performed as part of a study of the young stellar populations in the galaxies of the Local Group. Eleven WFPC2 pointings, with some overlap, cover two regions,…

Astrophysics · Physics 2009-11-11 L. Bianchi , B. Efremova

We reassess the applicability of the Toomre criterion in galactic disks and we study the local star formation law in 16 disk galaxies for which abundance gradients are published. The data we use consists of stellar light profiles, atomic…

Astrophysics · Physics 2009-11-10 S. Boissier , N. Prantzos , A. Boselli , G. Gavazzi

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…

Astrophysics of Galaxies · Physics 2014-11-26 F. Fusco , R. Buonanno , S. L. Hidalgo , A. Aparicio , A. Pietrinferni , G. Bono , M. Monelli , S. Cassisi

We present a wide-field, high spatial and velocity resolution map of the entire extended HI distribution of the Local Group dwarf galaxy NGC 6822. The observations were obtained with the Australia Telescope Compact Array in mosaicing mode.…

Astrophysics · Physics 2009-10-31 W. J. G. de Blok , F. Walter
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