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Related papers: The most metal poor stars

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Cosmological models predict the oldest stars in the Galaxy should be found closest to the centre of the potential well, in the bulge. The EMBLA Survey successfully searched for these old, metal-poor stars by making use of the distinctive…

Exo-planets are preferentially found around high metallicity main sequence stars. We aim at investigating whether evolved stars share this property, and what this tells about planet formation. Statistical tools and the basic concepts of…

Observations show that galaxies follow a mass-metallicity relation over a wide range of masses. One currently favoured explanation is that less massive galaxies are less able to retain the gas and stellar ejecta and thus may lose the…

Astrophysics · Physics 2008-11-26 J. Koeppen , C. Weidner , P. Kroupa

We have measured the mass of metals in the molecular gas in 13 submillimetre galaxies at z~4 in which the gas, based on previous observations, lies in a cold rotating disk. We measured the metal masses using either the submillimetre line or…

Astrophysics of Galaxies · Physics 2024-06-24 Stephen Eales , Haley Gomez , Loretta Dunne , Simon Dye , Matthew W. L. Smith

Accurate relative abundances have been obtained for a sample of 21 mildly metal-poor stars from the analysis of high resolution and high signal-to-noise spectra. With these accurate results, correlations between relative abundances have…

Astrophysics · Physics 2007-05-23 E. Jehin , P. Magain , C. Neuforge , A. Noels , G. Parmentier , A. Thoul

We present a new analysis of the abundances observed in extremely metal poor stars based on both a new generation of theoretical presupernova models and explosions of zero metallicity massive stars and a new abundance analysis of an…

Astrophysics · Physics 2007-05-23 Marco Limongi , Alessandro Chieffi

We report on the discovery of seven low-metallicity stars selected from the Hamburg/ESO Survey, six of which are extremely metal-poor ([Fe/H]<-3.0), with four having [Fe/H]<-3.5. Chemical abundances or upper limits are derived for these…

Context. The study of old, metal-poor stars deepens our knowledge on the early stages of the universe. In particular, the study of these stars gives us a valuable insight into the masses of the first massive stars and their emission of…

Solar and Stellar Astrophysics · Physics 2021-10-04 A. Matas Pinto , M. Spite , E. Caffau , P. Bonifacio , L. Sbordone , T. Sivarani , M. Steffen , F. Spite , P. Francois , P. Di Matteo

We present extensive calculations of the structure and the evolution of low-massstars in the range 0.07-0.8 $\msol$, for metallicities $-2.0\le \mh \le 0.0$. These calculations are based on the most recent description of the microphysics…

Astrophysics · Physics 2008-11-26 Gilles Chabrier , Isabelle Baraffe

The early Universe had a chemical composition consisting of hydrogen, helium and traces of lithium1, almost all other elements were created in stars and supernovae. The mass fraction, Z, of elements more massive than helium, is called…

Multiple generations of massive stars have lived and died during Cosmic History, invigorating host galaxies with ionizing photons, kinetic energy, fresh material and stellar-size black holes. At present, massive stars in the Small…

Solar and Stellar Astrophysics · Physics 2019-03-14 M. Garcia , C. J. Evans , A. Wofford , J. C. Bouret , N. Castro , M. Cerviño , A. W. Fullerton , A. Herrero , D. J. Lennon , F. Najarro

Low and intermediate mass stars with super solar metallicities comprise a known portion of the universe. Yet yields for asymptotic giant branch (AGB) stars with metallicities greater than $Z=0.04$ do not exist in the literature. This…

Solar and Stellar Astrophysics · Physics 2023-08-14 Giulia C. Cinquegrana , Amanda I. Karakas

We performed a detailed study of the ratio of low-{\alpha} to high-{\alpha} stars in the Galactic halo as observed by the Gaia-ESO Survey. Using a sample of 381 metal-poor stars from the second internal data release, we found that the value…

The ages of the oldest and most metal-poor stars in the Milky Way bear important information on the age of the Universe and its standard model. We analyze a sample of 28 extremely metal-poor field stars in the solar vicinity culled from the…

Solar and Stellar Astrophysics · Physics 2022-12-07 Anastasiia Plotnikova , Giovanni Carraro , Sandro Villanova , Sergio Ortolani

A stochastic model of the chemical enrichment of metal-poor systems by core-collapse (Type II) supernovae is presented, allowing for large-scale mixing of the enriched material by turbulent motions and cloud collisions in the interstellar…

Astrophysics · Physics 2009-11-11 T. Karlsson

Ground- and space-based observations of stellar heavy element abundances are providing a clearer picture of the chemical evolution of the Galaxy. A large number of (r)apid and (s)low neutron capture process elements, including the first…

Astrophysics · Physics 2007-05-23 John J Cowan , Christopher Sneden , James W Truran , Debra L Burris

Li abundances in the bulk of low-mass metal-poor stars are well reproduced by stellar evolution models adopting a constant initial abundance. However, a small number of stars have exceptionally high Li abundances, for which no convincing…

Solar and Stellar Astrophysics · Physics 2018-01-31 Haining Li , Wako Aoki , Tadafumi Matsuno , Yerra Bharat Kumar , Jianrong Shi , Takuma Suda , Gang Zhao

Chemically peculiar stars define a class of stars that show unusual elemental abundances due to stellar photospheric effects and not due to natal variations. In this paper, we compare the elemental abundance patterns of the ultra metal-poor…

Astrophysics · Physics 2009-11-13 K. A. Venn , D. L. Lambert

A substantial fraction of metal-poor stars in the local Milky Way halo exhibit large overabundances of carbon. These stars, dubbed Carbon-Enhanced Metal-Poor (CEMP) stars, provide crucial constraints on the nature of the early universe…

Several planets have recently been discovered around old metal-poor stars, implying that these planets are also old, formed in the early Universe. The canonical theory suggests that the conditions for their formation could not have existed…

Earth and Planetary Astrophysics · Physics 2016-03-21 Yu. A. Shchekinov , M. Safonova , J. Murthy
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