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Related papers: A continuous low star formation rate in IZw 18 ?

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Understanding the chemical enrichment of different elements is crucial to gaining a complete picture of galaxy chemical evolution. In this study, we present a new sample of 46 low-redshift, low-mass star-forming galaxies at $M_*\sim…

We have analyzed the properties of the star formation episodes taking place in a sample of Blue Compact and Irregular galaxies by comparing their multiwavelength observational properties with the predictions of evolutionary population…

Astrophysics · Physics 2007-05-23 J. M. Mas-Hesse , D. Kunth

We present results from near-infrared spectroscopy of 26 emission-line galaxies at z ~ 2 obtained with the FIRE spectrometer on the Magellan Baade telescope. The sample was selected from the WISP survey, which uses the near-infrared grism…

We present magnesium abundances derived from high resolution spectra using several Mg I and two high excitation Mg II lines for 19 metal-poor stars with [Fe/H] values between -1.1 and +0.2. The main goal is to search for systematic…

Astrophysics · Physics 2016-08-30 Carlos Abia , Lyudmila Mashonkina

There has been great progress in recent years in discovering star forming galaxies at high redshifts (z>5), close to the epoch of reionization of the intergalactic medium (IGM). The WFC3 and ACS cameras on the Hubble Space Telescope have…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Andrew Bunker

Local starbursts have a higher efficiency of converting gas into stars, as compared to typical star-forming galaxies at a given stellar mass, possibly indicative of different modes of star formation. With the peak epoch of galaxy formation…

We use new studies of the cosmic evolution of star-forming galaxies to estimate the production rate of ionizing photons from hot, massive stars at low and intermediate redshifts. The luminosity function of blue galaxies in the Canada-France…

Astrophysics · Physics 2015-06-24 E. Giallongo , A. Fontana , P. Madau

The inner few hundred parsecs of the Milky Way harbours gas densities, pressures, velocity dispersions, an interstellar radiation field and a cosmic ray ionisation rate orders of magnitude higher than the disc; akin to the environment found…

Astrophysics of Galaxies · Physics 2017-06-21 A. T. Barnes , S. N. Longmore , C. Battersby , J. Bally , J. M. D. Kruijssen , J. D. Henshaw , D. L. Walker

We have characterized the physical properties (electron temperature, density, metallicity) of the ionized gas and the ionizing population (age, metallicity, presence of WR stars) in the Lynx arc at z=3.36. This is a low metallicity (~10%…

Astrophysics · Physics 2009-11-10 Montse Villar-Martin , Miguel Cervino , Rosa Gonzalez Delgado

Early quiescent galaxies at z~2 are known to be remarkably compact compared to their nearby counterparts. Possible progenitors of these systems include galaxies that are structurally similar, but are still rapidly forming stars. Here, we…

While all models for the evolution of galaxies require the accretion of gas to sustain their growth via on-going star formation, it has proven difficult to directly detect this inflowing material. In this paper we use data of nearby…

The chemical composition of galaxies has been measured out to z~4. However, nearly all studies beyond z~0.7 are based on strong-line emission from HII regions within star-forming galaxies. Measuring the chemical composition of distant…

We examine the evolutionary status of luminous, star-forming galaxies in intermediate-redshift clusters by considering their star formation rates and the chemical and ionsiation properties of their interstellar emitting gas. Our sample…

Astrophysics · Physics 2009-11-11 M. Mouhcine , S. P. Bamford , A. Aragon-Salamanca , O. Nakamura

The warm ionized gas in low-mass, metal-poor starforming galaxies is chemically homogeneous despite the prevalence of large H II regions which contain hundreds of evolved massive stars, supernovae, and Wolf-Rayet stars with…

Astrophysics · Physics 2007-05-23 Henry A. Kobulnicky

We derive oxygen abundances for a sample of 40 luminous (M_{B} < -19), star-forming, mostly disk, field galaxies with redshifts in the range 0.2 < z < 0.8$, with a median of <z> = 0.45. Oxygen abundances, relative to hydrogen, of the…

Astrophysics · Physics 2009-11-11 M. Mouhcine , S. P. Bamford , A. Aragon-Salamanca , O. Nakamura

The abundances of iron and oxygen are homogeneously determined in a sample of 523 nearby (d<150 pc) FGK disk and halo stars with metallicities in the range -1.5<[Fe/H]<0.5. The oxygen abundances were inferred from a restricted non-LTE…

Astrophysics · Physics 2009-11-13 I. Ramirez , C. Allende Prieto , D. L. Lambert

We report on the discovery of 28 $z\approx0.8$ metal-poor galaxies in DEEP2. These galaxies were selected for their detection of the weak [OIII]$\lambda$4363 emission line, which provides a "direct" measure of the gas-phase metallicity. A…

Astrophysics of Galaxies · Physics 2015-05-27 Chun Ly , Jane Rigby , Michael Cooper , Renbin Yan

The central star-forming regions in three blue compact dwarf galaxies (He 2-10, NGC 5253, and II Zw 40) were observed in the 340 GHz (880 micron) band at 5 arcsec resolution with the Submillimetre Array (SMA). Continuum emission associated…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Hiroyuki Hirashita

Stars form from cold molecular interstellar gas. Since this is relatively rare in the local Universe, galaxies like the Milky Way form only a few new stars per year. Typical massive galaxies in the distant Universe formed stars an order of…

Four recent observational results have challenged our understanding of high--redshift galaxies, as they require the presence of far more ultraviolet photons than should be emitted by normal stellar populations. First, there is significant…

Astrophysics · Physics 2009-11-11 Raul Jimenez , Zoltan Haiman
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