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Related papers: Lithium-rich giants in the Sagittarius dSph Tidal …

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We investigate the properties of 1262 red giant stars with high photospheric abundances of lithium observed by the GALAH and \Ktwo-HERMES surveys, and discuss them in the context of proposed mechanisms for lithium enrichment and…

We present evidence that nearly half of the dwarf spheroidal galaxies (dSph and dSph/dIrr) in the Local Group are associated with large reservoirs of atomic gas, in some cases larger than the stellar mass. The gas is sometimes found at…

Astrophysics · Physics 2009-10-31 Leo Blitz , Timothy Robishaw

I summarize the results of 15 years of research on the surface abundances of stars in globular clusters. Globular-cluster stars afford a unique view of the physical processes that shape the surface abundances of stars on and beyond the…

Solar and Stellar Astrophysics · Physics 2021-11-02 A. J. Korn

Two giants of the Sagittarius dwarf spheroidal have been observed with the UVES spectrograph on the ESO 8.2m Kueyen telescope, during the commissioning of the instrument. Sgr 139 has [Fe/H]=-0.28 and Sgr 143 [Fe/H]=-0.21, these values are…

Dwarf galaxies like Sagittarius (Sgr) provide a unique window into the early stages of galactic chemical evolution, particularly through their metal-poor stars. By studying the chemical abundances of stars in the Sgr core and tidal streams,…

Astrophysics of Galaxies · Physics 2025-01-27 Xiaowei Ou , Alexander Yelland , Anirudh Chiti , Anna Frebel , Guilherme Limberg , Mohammad K. Mardini

Stars aligned in thin stream-like features (feathers), with widths of $\delta\sim1-10^{\circ}$ and lengths as large as $\Delta l\sim180^{\circ}$, have been observed towards the Anticenter of our Galaxy and their properties mapped in…

Astrophysics of Galaxies · Physics 2018-09-05 Chervin F. P. Laporte , Kathryn V. Johnston , Anastasios Tzanidakis

According to standard stellar evolution, lithium is destroyed throughout most of the evolution of low- to intermediate-mass stars. However, a number of evolved stars on the red giant branch (RGB) and the asymptotic giant branch (AGB) are…

Solar and Stellar Astrophysics · Physics 2012-06-14 Stefan Uttenthaler , Thomas Lebzelter , Maurizio Busso , Sara Palmerini , Bernhard Aringer , Mathias Schultheis

The lithium abundances for 378 G/K giants are derived with non-LTE correction considered. Among these, there are 23 stars that host planetary systems. The lithium abundance is investigated, as a function of metallicity, effective…

Solar and Stellar Astrophysics · Physics 2015-06-19 Y. J. Liu , K. F. Tan , L. Wang , G. Zhao , Bun'ei Sato , Y. Takeda , H. N. Li

Mapping lithium evolution for evolved stars will provide restrictions and constraints on the fundamental stellar interior physical processes, which further shed light on our understanding of the theory of stellar structure and evolution.…

Solar and Stellar Astrophysics · Physics 2021-09-29 Jinghua Zhang , Jian-Rong Shi , Hong-Liang Yan , Yaguang Li , Qi Gao , Chun-Qian Li , Xianfei Zhang , Shuai Liu , Shaolan Bi , Gang Zhao , Yan Li

The main aim of this paper is to report two new detections of tidal debris in the northern stream of the Sagittarius dwarf galaxy located at 45 arcdeg and 55 arcdeg from the center of galaxy. Our observational approach is based on deep…

Astrophysics · Physics 2009-11-10 D. Martinez-Delgado , M. A. Gomez-Flechoso , A. Aparicio , R. Carrera

The existence of one percent of lithium-rich giant stars among normal, lithium-poor giant stars continues to be poorly explained. By merging two catalogues, one containing 10,535 lithium-rich giant stars with lithium abundances ranging from…

Solar and Stellar Astrophysics · Physics 2024-12-09 R. de la Reza

The lithium abundance in 62 halo dwarfs is determined from accurate equivalent widths reported in the literature and an improved infrared flux method (IRFM) temperature scale. The Li abundance of 41 plateau stars (those with Teff > 6000 K)…

Astrophysics · Physics 2009-11-10 Jorge Melendez , Ivan Ramirez

The presence of a large amount of Li in giants is still a mystery. Most of the super Li-rich giants reported in recent studies are in the solar metallicity regime. Here, we study the five metal-poor super Li-rich giants (SLRs) from GALAH…

Solar and Stellar Astrophysics · Physics 2024-03-26 Antony Susmitha , Anohita Mallick , Bacham E. Reddy

We present FLAMES/GIRAFFE spectroscopy obtained at the Very Large Telescope (VLT). Using these observations we have been able for the first time to observe the Li I doublet in the Main Sequence stars of a Globular Cluster. We also observed…

Astrophysics of Galaxies · Physics 2015-05-14 J. I. González Hernández , P. Bonifacio , E. Caffau , M. Steffen , H. -G. Ludwig , N. Behara , L. Sbordone , R. Cayrel , S. Zaggia

Lithium abundances in a sample of halo dwarfs have been redetermined by using the new T$_{eff}$ derived by Fuhrmann et al (1994) from modelling of the Balmer lines. These T$_{eff}$ are reddening independent, homogeneous and of higher…

Astrophysics · Physics 2007-05-23 P. Molaro , F. Primas , P. Bonifacio

Lithium has confused scientists for decades at almost each scale of the universe. Lithium-rich giants are peculiar stars with lithium abundances over model prediction. A large fraction of lithium-rich low-mass evolved stars are…

We report on the determination of the lithium abundance [A(Li)] of 52 solar-like stars. For 41 objects the A(Li) here presented corresponds to the first measurement. We have measured the equivalent widths of the 6708\AA\ lithium feature in…

Solar and Stellar Astrophysics · Physics 2015-07-07 R. López-Valdivia , J. B. Hernández-Águila , E. Bertone , M. Chávez , F. Cruz-Saenz de Miera , E. M. Amazo-Gómez

Lithium and zirconium abundances (the latter taken as representative for s-process enrichment) are determined for a large sample of massive Galactic O-rich AGB stars, for which high resolution optical spectroscopy has been obtained…

Astrophysics · Physics 2009-11-11 D. A. Garcia-Hernandez , P. Garcia-Lario , B. Plez , A. Manchado , F. D'Antona , J. Lub , H. Habing

Tidal streams of the Sagittarius dwarf spheroidal galaxy (Sgr) may be showering dark matter onto the solar system and contributing approx (0.3--23)% of the local density of our Galactic Halo. If the Sagittarius galaxy contains WIMP dark…

Astrophysics · Physics 2009-11-10 Katherine Freese , Paolo Gondolo , Heidi Jo Newberg

An all high-latitude sky survey for cool carbon giant stars in the Galactic halo has revealed 75 such stars, of which the majority are new detections. Of these, more than half are clustered on a Great Circle on the sky which intersects the…

Astrophysics · Physics 2009-10-31 Rodrigo Ibata , Geraint F. Lewis , Michael Irwin , Edward Totten , Thomas Quinn