Andromeda IV: A new local volume very metal-poor galaxy
نویسندگان
چکیده
منابع مشابه
New abundance measurements in UKS1927–177, a very metal-poor galaxy in the Local Group
We present new results from optical spectroscopy of the brightest Hii region in the dwarf irregular galaxy UKS1927–177 in Sagittarius (SagDIG). From high signal-to-noise spectra, reddening-corrected line flux ratios have been measured with typical uncertainties of a few percent, from which the oxygen abundance is rediscussed, and new abundance estimates are derived for N and Ne. The O abundance...
متن کاملObservations of Very Metal-Poor Stars in the Galaxy
I report on recent results from observations of stars with metallicities [Fe/H] ≤ −2.0. These include a substantial new sample of objects with high-resolution observations obtained as part of a follow-up of the HK Survey, The Hamburg/ESO Survey, and the ongoing survey SEGUE: Sloan Extension for Galactic Understanding and Exploration. Perspectives on the next directions are also provided.
متن کاملPulsating red giant and supergiant stars in the Local Group dwarf galaxy Andromeda I
We have conducted an optical long-term monitoring survey of the majority of dwarf galaxies in the Local Group, with the Isaac Newton Telescope (INT), to identify the long period variable (LPV) stars. LPV stars vary on timescales of months to years, and reach the largest amplitudes of their brightness variations at optical wavelengths, due to the changing temperature. They trace stellar populati...
متن کاملMetal-Poor Globular Clusters and Galaxy Formation
We demonstrate a significant (> 5σ) correlation between the mean color of metalpoor globular cluster (GC) systems and parent galaxy luminosity. A Bayesian Markov Chain Monte Carlo method is introduced to find the mean color, and is easily generalizable to quantify multimodality in other astronomical datasets. We derive a GC color– galaxy luminosity relation of the form Z ∝ L. When combined with...
متن کاملSulphur abundance in very metal-poor stars
We have obtained high-resolution high signal-to-noise spectra of the S i nearinfrared doublet at 8694 Å in eight metal-poor stars with metallicities in the range −0.6 ≤[Fe/H]≤ −3.0. Elemental sulphur abundances were derived for six targets and upper limits were set for two of the most metal-poor stars in the sample. The sulphur doublet at 8694.62 Å has been detected in three stars (HD19445, HD2...
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ژورنال
عنوان ژورنال: Astrophysical Bulletin
سال: 2008
ISSN: 1990-3413,1990-3421
DOI: 10.1134/s1990341308020028