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Related papers: Star Formation in Dwarf Irregular Galaxies: NGC 68…

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We present a pilot narrow-band survey of H-alpha emitters at z=2.2 in the Great Observatories Origins Deep Survey North (GOODS-N) field with MOIRCS instrument on the Subaru telescope. The survey reached a 3 sigma limiting magnitude of 23.6…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Ken-ichi Tadaki , Tadayuki Kodama , Yusei Koyama , Masao Hayashi , Ichi Tanaka , Chihiro Tokoku

(Abridged). We present HST photometry of the late-type dwarf galaxy NGC 1705 observed with the WFPC2 in the U and B bands, and with the ACS/HRC in the U, V, and I bands. We cross-correlate these data with previous ones acquired with the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 F. Annibali , M. Tosi , M. Monelli , M. Sirianni , P. Montegriffo , A. Aloisi , L. Greggio

Chemical evolution models are useful for understanding the formation and evolution of stars and galaxies. Model predictions will be more robust as more observational constraints are used. We present chemical evolution models for the dwarf…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-31 Liliana Hernandez-Martinez , Leticia Carigi , Miriam Peña , Manuel Peimbert

The Survey of HI in Extremely Low-mass Dwarfs (SHIELD) is an on-going multi-wavelength program to characterize the gas, star formation, and evolution in gas-rich, very low-mass galaxies that populate the faint end of the galaxy luminosity…

The main characteristics of a wide photometric survey of the Sgr dwarf spheroidal galaxy are shortly presented. V and I photometry has been obtained for ~ 90000 stars toward Sgr and for ~ 9000 stars in a region devoid of Sgr stars (for…

Astrophysics · Physics 2007-05-23 M. Bellazzini , F. R. Ferraro , R. Buonanno

Spectra that cover wavelengths from 0.6 to 1.1um are used to examine the behavior of emission and absorption features in a contiguous 22 x 300 arcsec region centered on the nearby dwarf galaxy NGC 55. Based on the relative strengths of…

Astrophysics of Galaxies · Physics 2019-08-07 T. J. Davidge

Results are presented of a study of the variable star populations in the dwarf spheroidal galaxy Leo I and in the dwarf irregular galaxy NGC 6822, based on time series photometry obtained with the Wide Field Imager of the 2.2 m ESO/MPI…

Astrophysics · Physics 2007-05-23 L. Baldacci , F. Matonti , L. Rizzi , G. Clementini , E. V. Held , Y. Momany , L. Di Fabrizio , I. Saviane

We present a wide-field, high spatial and velocity resolution map of the entire extended HI distribution of the nearby Local Group dwarf galaxy NGC 6822. The observations were obtained with the Parkes single-dish telescope and the Australia…

Astrophysics · Physics 2007-05-23 W. J. G. de Blok , F. Walter

We present the results of deep high resolution imaging performed with ACS/HRC@HST in the most active region of the nearby starburst galaxy NGC 4214. We resolved the stellar populations of five Young Massive Clusters and their surrounding…

Astrophysics of Galaxies · Physics 2015-06-17 A. Sollima , M. Cignoni , R. G. Gratton , M. Tosi , A. Bragaglia , S. Lucatello , G. Meurer

Small amounts of star formation in elliptical galaxies are suggested by several results: surprisingly young ages from optical line indices, cooling X-ray gas, and mid-IR dust emission. Such star formation has previously been difficult to…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 H. Alyson Ford , Joel N. Bregman

We derive and analyse the star formation histories of 393 intermediate-redshift (0.1 $\leq$ z $\leq$ 0.9) galaxies with stellar masses between $\sim$10$^{8}$ - 10$^{12}$ M$_{\odot}$. We probe a cosmic time of approximately 6 Gyr and a range…

We study star-formation-inducing mechanisms in galaxies through multi- wavelength measurements of a sample of dwarf galaxies in the Virgo cluster described in paper I. Our main goal is to test how star formation inducing mechanisms depend…

Astrophysics · Physics 2008-02-03 Elchanan Almoznino , Noah Brosch

We report on the X-ray evolution over the last ~9 Gyr of cosmic history (i.e., since z = 1.4) of late-type galaxy populations in the Chandra Deep Field-North and Extended Chandra Deep Field-South (CDF-N and E-CDF-S, respectively; jointly…

What can we learn from the somewhat arduous study of old stellar populations in nearby galaxies? Unless the nearby universe is subtly anomalous, it should contain a relatively normal selection of galaxies whose histories are representative…

Astrophysics · Physics 2009-10-31 Eline Tolstoy

We have extracted PSF-fitted stellar photometry from near-ultraviolet, optical and near-infrared images, obtained with the Hubble Space Telescope, of the nearby (D ~ 5.5 Mpc) SBm galaxy NGC 1311. The ultraviolet and optical data reveal a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Paul B. Eskridge , Rogier A. Windhorst , Violet A. Mager , Rolf A. Jansen

We present the results of a detailed optical and near-IR study of the nearby star-forming dwarf galaxy NGC4214. We discuss the stellar content, drawing particular attention to the intermediate-age and/or old field stars, which are used as a…

We present near-IR spectroscopy of red supergiant (RSG) stars in NGC 6822, obtained with the new VLT-KMOS instrument. From comparisons with model spectra in the J-band we determine the metallicity of 11 RSGs, finding a mean value of [Z] =…

Solar and Stellar Astrophysics · Physics 2015-06-23 L. R. Patrick , C. J. Evans , B. Davies , R-P. Kudritzki , J. Z. Gazak , M. Bergemann , B. Plez , A. M. N. Ferguson

To explore the properties of extreme outer stellar disks, we obtained ultra-deep V and GALEX UV images of 4 dwarf irregular galaxies and one Blue Compact Dwarf galaxy and ultra-deep B images of 3 of these. Our V-band surface photometry…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Deidre A. Hunter , Bruce G. Elmegreen , Se-Heon Oh , Ed Anderson , Tyler E. Nordgren , Philip Massey , Nick Wilsey , Malanka Riabokin

Broad-band near-infrared images are used to probe the photometric properties of the brightest asymptotic giant branch (AGB) stars within 2 arcminutes of the centers of the dwarf elliptical galaxies NGC 147, NGC 185, and NGC 205. Based on…

Astrophysics · Physics 2008-11-26 T. J. Davidge

We present a new method to derive 2D star formation histories in dwarf irregular galaxies. Based on multicolor stellar photometry data we have found that in the Leo A galaxy during the last $\sim$400 Myr star formation was propagating…

Astrophysics of Galaxies · Physics 2019-11-06 Marius Čeponis , Rima Stonkutė , Vladas Vansevičius