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Related papers: Lithium abundances in globular clusters

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The abundance of primordial lithium is derived from the observed spectroscopy of metal-poor stars in the galactic halo. However, the observationally inferred abundance remains at about a factor of three below the abundance predicted by…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-30 G. J. Mathews , A. Kedia , N. Sasankan , M. Kusakabe , Y. Luo , T. Kajino , D. G. Yamazaki , T. Makki , M. El Eid

Observations of low-metallicity halo stars have revealed a puzzling result: the abundance of \li7 in these stars is at least three times lower than their predicted primordial abundance. It is unclear whether the cause of this disagreement…

Astrophysics of Galaxies · Physics 2015-06-12 Tijana Prodanovic , Tamara Bogdanovic , Dejan Urosevic

We review the state of the art in modelling lithium production, through the Cameron-Fowler mechanism, in two stellar sites: during nova explosions and in the envelopes of massive asymptotic giant branch (AGB) stars. We also show preliminary…

Astrophysics of Galaxies · Physics 2015-05-18 F. D'Antona , P. Ventura

Theoretical models of stellar evolution predict that most of the lithium inside a star is destroyed as the star becomes a red giant. However, observations reveal that about 1% of red giants are peculiarly rich in lithium, often exceeding…

Recently, we studied the chemical evolution of lithium in the thin disc of the Milky Way. We found that the best agreement with the observed Li abundances in the thin disc is obtained considering novae as the main source of lithium. We…

Solar and Stellar Astrophysics · Physics 2020-04-15 G. Cescutti , P. Molaro , X. Fu

The majority of the inhomogeneities in the chemical composition of Globular Cluster (GC) stars appear due to primordial enrichment by hot-CNO cycled material processed in stars belonging to a first stellar generation. Either massive AGB…

Astrophysics · Physics 2009-11-13 F. D'Antona , V. Caloi

The current status of observational studies of lithium depletion in open clusters is reviewed, concentrating mainly on G and K type stars. I attempt to answer the following questions: Can the lithium depletion patterns seen in open clusters…

Astrophysics · Physics 2007-05-23 R. D. Jeffries

We investigate the viability of a model in which the chemical anomalies among Globular Cluster stars are due to accretion of gas onto the protostellar discs of low mass stars. This model has been suggested as a way to reduce the large…

Solar and Stellar Astrophysics · Physics 2015-06-22 Francesca D'Antona , Paolo Ventura , Thibaut Decressin , Enrico Vesperini , Annibale D'Ercole

Standard stellar evolution model predicts a severe depletion of lithium (Li) abundance during the first dredge up process (FDU). Yet a small fraction of giant stars are still found to preserve a considerable amount of Li in their…

Solar and Stellar Astrophysics · Physics 2020-01-08 Qi Gao , Jian-Rong Shi , Hong-Liang Yan , Tai-Sheng Yan , Mao-Sheng Xiang , Yu-Tao Zhou , Chun-Qian Li , Gang Zhao

Lithium abundances in open clusters are a very effective probe of mixing processes, and their study can help to understand the large depletion of lithium in the Sun. Due to its age and metallicity, the open cluster M67 is especially…

Solar and Stellar Astrophysics · Physics 2015-06-04 Giancarlo Pace , Matthieu Castro , Jorge Melendez , Sylvie Theado , Jose-Dias do Nascimento

Following the observations of Israelian et al. 2004, we compare different evolutionary models in order to study the lithium destruction processes and the planetary formation scenarii.

Astrophysics · Physics 2009-11-11 M. Castro , O. Richard , S. Vauclair

The first generation of stars is quite unique. The absence of metals likely affects their formation, with current models suggesting a much more top-heavy initial mass fraction than what we observe today, and some of their other properties,…

Solar and Stellar Astrophysics · Physics 2020-02-13 Alexander Heger , Stan Woosley

Many scenarios for the origin of the chemical anomalies observed in globular clusters (GCs; i.e., multiple populations) require that GCs were much more massive at birth, up to $10-100\times$, than they are presently. This is invoked in…

Astrophysics of Galaxies · Physics 2015-08-19 Nate Bastian , Carmela Lardo

We aim to constrain the mixing processes in low-mass stars by investigating the behaviour of the Li surface abundance after the main sequence. We take advantage of the data from the sixth internal data release of Gaia-ESO, idr6, and from…

Recent observational studies have revealed star-to-star abundance inhomogeneity among light elements (e.g., C, N, O, Na, and Al) of stars on the main sequence in the Galactic globular clusters (GCs). One of promising interpretations for…

Astrophysics · Physics 2009-11-13 Kenji Bekki

The determination of Li and proton-capture element abundances in globular cluster (GC) giants allows us to constrain several key questions on the multiple population scenarios in GCs, from formation and early evolution, to pollution and…

Solar and Stellar Astrophysics · Physics 2015-05-19 Valentina D'Orazi , Anna F. Marino

We study the temporal evolution of the 7Li abundance in the gaseous medium for all the components (halo, disk and bulge) of our Galaxy. We adopt nucleosynthesis prescriptions on stellar lithium production based upon recent observational…

Astrophysics · Physics 2016-08-30 Donatella Romano

The Gaia-ESO Survey (GES) is a large public spectroscopic survey that was carried out using the multi-object FLAMES spectrograph at the Very Large Telescope. The survey provides accurate radial velocities, stellar parameters, and elemental…

Context. The abundance inhomogeneities of light elements observed in Globular Clusters (GCs), and notably the ubiquitous Na-O anti-correlation, are generally interpreted as evidence that GCs comprise several generations of stars. There is…

Solar and Stellar Astrophysics · Physics 2015-05-30 L. Monaco , S. Villanova , P. Bonifacio , E. Caffau , D. Geisler , G. Marconi , Y. Momany , H. -G. Ludwig

We discuss the self-enrichment scenario by AGB stars for the formation of multiple populations in globular clusters (GCs) by analyzing data set of giant stars observed in 9 Galactic GCs, covering a wide range of metallicities and for which…