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相关论文: The cosmological Lithium problem outside the Galax…

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We present Li, Na, Al and Fe abundances of 199 lower red giant branch stars members of the stellar system Omega Centauri, using high-resolution spectra acquired with FLAMES at the Very Large Telescope. The A(Li) distribution is peaked at…

太阳与恒星天体物理 · 物理学 2018-10-31 A. Mucciarelli , M. Salaris , L. Monaco , P. Bonifacio , X. Fu , S. Villanova

Context: In order to study the evolution of Li in the Galaxy it is necessary to observe dwarf or subgiant stars. Abridged Although Li has been extensively studied in the Galactic disk and halo, to date there is only one uncertain detection…

星系天体物理 · 物理学 2015-05-20 T. Bensby , M. Asplund , J. A. Johnson , S. Feltzing , J. Meléndez , S. Dong , A. Gould , C. Han , D. Adén , S. Lucatello , A. Gal-Yam

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…

太阳与恒星天体物理 · 物理学 2015-07-07 R. López-Valdivia , J. B. Hernández-Águila , E. Bertone , M. Chávez , F. Cruz-Saenz de Miera , E. M. Amazo-Gómez

Although red giants deplete lithium on their surfaces, some giants are Li-rich. Intermediate-mass asymptotic giant branch (AGB) stars can generate Li through the Cameron-Fowler conveyor, but the existence of Li-rich, low-mass red giant…

太阳与恒星天体物理 · 物理学 2016-03-10 Evan N. Kirby , Puragra Guhathakurta , Andrew J. Zhang , Jerry Hong , Michelle Guo , Rachel Guo , Judith G. Cohen , Katia Cunha

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…

宇宙学与河外天体物理 · 物理学 2020-06-30 G. J. Mathews , A. Kedia , N. Sasankan , M. Kusakabe , Y. Luo , T. Kajino , D. G. Yamazaki , T. Makki , M. El Eid

The "stellar" solution to the cosmological lithium problem proposes that surface depletion of lithium in low-mass, metal-poor stars can reconcile the lower abundances found for Galactic halo stars with the primordial prediction. Globular…

太阳与恒星天体物理 · 物理学 2015-05-18 K. Lind , F. Primas , C. Charbonnel , F. Grundahl , M. Asplund

Lithium depletion and enrichment in the cosmos is not yet well understood. To help tighten constraints on stellar and Galactic evolution models, we present the largest high-resolution analysis of Li abundances A(Li) to date, with results…

In this contribution we discuss the use of the surface Li abundance in lower RGB stars as alternative diagnostic of the primordial Li abundance. These stars are located in the portion of the RGB after the completion of the First Dredge-Up…

太阳与恒星天体物理 · 物理学 2012-05-14 A. Mucciarelli , M. Salaris , P. Bonifacio

Lithium is a fragile but crucial chemical element in the universe, exhibits interesting and complex behaviors. Thanks to the massive spectroscopic data from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST)…

To alleviate the discrepancy between the prediction of the primordial lithium abundance in the universe and the abundances observed in Pop II dwarfs and subgiant stars, it has been suggested that the stars observable today have undergone…

太阳与恒星天体物理 · 物理学 2015-05-13 K. Lind , F. Primas , C. Charbonnel , F. Grundahl , M. Asplund

The role of novae as producers of galactic lithium has been suggested since the 1970s, and it has been reconsidered recently with the detection of $^7$Be in their outbursts. At the same time, stellar models are moving forward to comprehend…

星系天体物理 · 物理学 2025-11-19 C. T. Nguyen , G. Cescutti , F. Matteucci , F. Rizzuti , A. Mucciarelli , D. Romano , L. Magrini , A. J. Korn , A. Bressan , L. Girardi

The source of the Galactic Lithium (Li) has long been a puzzle. With the discovery of Li in novae, extensive research has been conducted. However, there still exists a significant disparity between the observed abundance of lithium in novae…

太阳与恒星天体物理 · 物理学 2024-06-25 Jun Gao , Chunhua Zhu , Guoliang Lü , Jinlong Yu , Lin Li , Helei Liu , Sufen Guo

The presence of multiple populations in globular clusters has been well established thanks to high-resolution spectroscopy. It is widely accepted that distinct populations are a consequence of different stellar generations: intra-cluster…

太阳与恒星天体物理 · 物理学 2015-06-24 V. D'Orazi , R. G. Gratton , G. C. Angelou , A. Bragaglia , E. Carretta , J. C. Lattanzio , S. Lucatello , Y. Momany , A. Sollima , G. Beccari

The observed lithum (Li) abundance of Galactic halo stars mainly fall within the range of 2.0--2.4 dex. This nearly constant value, known as the Spite plateau, is approximately a factor of three lower than the value predicted from cosmic…

太阳与恒星天体物理 · 物理学 2026-02-27 Wuming Yang , Shuya Dou , Xiangcun Meng , Yaqian Wu , Shaolan Bi

About one percent of giants\upcite{Brown1989} are detected to have anomalously high lithium (Li) abundances in their atmospheres, conflicting directly with the prediction of the standard stellar evolution models\upcite{Iben1967}, and making…

We review three Li problems. First, the Li problem in the Sun, for which some previous studies have argued that it may be Li-poor compared to other Suns. Second, we discuss the Li problem in planet hosting stars, which are claimed to be…

太阳与恒星天体物理 · 物理学 2010-11-22 J. Melendez , I. Ramirez , L. Casagrande , M. Asplund , B. Gustafsson , D. Yong , J. D. do Nascimento , M. Castro , M. Bazot

aims: Our aim is to determine Li abundances in TO stars of the Globular Cluster 47 Tuc and test theories about Li variations among TO stars. method: We make use of high resolution (R~ 43000), high signal-to-noise ratio (S/N=50--70) spectra…

In the globular cluster NGC2808, a quasi-standard initial lithium abundance is derived for a red giant belonging to the `extreme' population, characterized by a large helium overabundance, and by abundances of proton capture elements…

Known sources of lithium (Li) in the universe include the big bang, novae, asymptotic giant branch stars, and cosmic ray spallation. During their longer-lived evolutionary phases, stars are not expected to add to the Li budget of the…

太阳与恒星天体物理 · 物理学 2022-07-20 Julio Chanamé , Marc H. Pinsonneault , Claudia Aguilera-Gómez , Joel C. Zinn

We test a scenario in which radial migration could affect the Li abundance pattern of dwarf stars in the solar neighbourhood. This may confirm that the Li abundance in these stars can not serve as a probe for the Li abundance in the…