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相关论文: COSMIC LITHIUM: GOING UP OR COMING DOWN ?

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Rapidly growing datasets from stellar spectroscopic surveys are providing unprecedented opportunities to analyse the chemical evolution history of our Galaxy. However, spectral analysis requires accurate modelling of synthetic stellar…

太阳与恒星天体物理 · 物理学 2024-03-29 J. W. E. Mallinson , K. Lind , A. M. Amarsi , K. Youakim

The lithium present in the photospheres of solar-type stars is transported to the inner parts by convection, reaching regions even somewhat below the convection zone, by non-standard transport mechanisms. In stars with deeper convective…

太阳与恒星天体物理 · 物理学 2023-05-04 Giulia Martos , Jorge Meléndez , Anne Rathsam , Gabriela Carvalho Silva

The evolution of the 7Li abundance in the Galaxy has been computed by taking into account several 7Li sources: novae, massive AGB stars, C-stars, Type II SNe and GCRs. The theoretical predictions for the evolution of the 7Li abundance in…

天体物理学 · 物理学 2011-05-23 D. Romano , F. Matteucci , P. Molaro , P. Bonifacio

The surface content of lithium (Li) and beryllium (Be) in stars can reveal important information about the temperature structure and physical processes in their interior regions. This study focuses on solar-type stars with a sample that is…

太阳与恒星天体物理 · 物理学 2022-12-14 Ann Merchant Boesgaard , Constantine P. Deliyannis , Michael G. Lum , Ashley Chontos

Recent detection of the isotope $^7$Be (that decays into $^7$Li) in the outburst of classical novae confirms the suggestion made in the 70s that novae could make $^7$Li. We reconsidered the role of novae as producers of Li by means of a…

太阳与恒星天体物理 · 物理学 2019-01-16 Gabriele Cescutti , Paolo Molaro

Lithium abundances in a selected sample of halo stars have been revised by using the new accurate IRFM effective temperatures by Alonso, Arribas & Martinez-Roger (1996a). From 41 plateau stars (Teff > 5700 and [Fe/H] <= -1.5) we found no…

天体物理学 · 物理学 2015-06-24 Piercarlo Bonifacio , Paolo Molaro

The surface abundance of lithium on the Sun is 140 times less than protosolar, yet the temperature at the base of the surface convective zone is not hot enough to burn Li. A large range of Li abundances in solar type stars of the same age,…

The temperature distribution of field Li-rich red giants suggests the presence of a population of Li-rich red clump (RC) stars. One proposed explanation for this population is that all stars with masses near 2 $M_\odot$ experience a…

太阳与恒星天体物理 · 物理学 2016-08-24 Joleen K. Carlberg , Katia Cunha , Verne V. Smith

Lithium is extensively known to be a good tracer of non-standard mixing processes occurring in stellar interiors. We present the results of a new large Lithium survey in red giant stars and combine it with surveys from the literature to…

太阳与恒星天体物理 · 物理学 2020-01-08 C. Charbonnel , N. Lagarde , G. Jasniewicz , P. North , M. Shetrone , J. Krugler Hollek , V. V. Smith , R. Smiljanic , A. Palacios , G. Ottoni

For the first time, we present an extensive study of stars with individual non-local thermodynamic equilibrium (NLTE) abundances for 17 chemical elements from Li to Eu in a sample of stars uniformly distributed over the $-2.62 \le$ [Fe/H]…

We present Li and Fe abundances for 87 stars in the GC M4,obtained with GIRAFFE high-resolution spectra. The targets range from the TO up to the RGB Bump. The Li abundance in the TO stars is uniform, with an average value A(Li)=2.30+-0.02…

太阳与恒星天体物理 · 物理学 2015-05-20 A. Mucciarelli , M. Salaris , L. Lovisi , F. R. Ferraro , L. Lanzoni , S. Lucatello , R. G. Gratton

An accurate value of the deuterium/hydrogen (D/H) ratio in the local interstellar medium (LISM) and a better understanding of the D/H variations with position in the Galactic disk can provide essential information on the primordial D/H…

天体物理学 · 物理学 2009-11-16 Jeffrey L. Linsky

The success of primordial nucleosynthesis has been limited by the long-standing Lithium problem. We use a self-consistent perturbative analysis of the effects of relevant theoretical parameters on primordial nucleosynthesis, including…

宇宙学与河外天体物理 · 物理学 2021-09-08 M. Deal , C. J. A. P. Martins

We present the first systematic study of lithium abundance in a chemically homogeneous sample of 27 red supergiants (RSGs) in the young Perseus complex. For these stars, accurate stellar parameters and detailed chemical abundances of iron…

太阳与恒星天体物理 · 物理学 2022-06-06 C. Fanelli , L. Origlia , A. Mucciarelli , N. Sanna , E. Oliva , E. Dalessandro

Using the cosmological constants derived from WMAP, the standard big bang nucleosynthesis (SBBN) predicts the light elements primordial abundances for 4He, 3He, D, 6Li and 7Li. These predictions are in satisfactory agreement with the…

宇宙学与河外天体物理 · 物理学 2012-08-13 M. Spite , F. Spite , P. Bonifacio

The discrepancy between the theoretical prediction of primordial lithium abundances and astronomical observations is called the Lithium Problem. We find that extra contributions from non-thermal hydrogen and helium during Big Bang…

宇宙学与河外天体物理 · 物理学 2020-03-31 Ming-Ming Kang , Yang Hu , Hong-Bo Hu , Shou-Hua Zhu

I shall review what has been learnt during 20 years of lithium observations in stars belonging to metal-poor globular clusters. The focus will be on little evolved main-sequence, turnoff-point (TOP) and subgiant-branch (SGB) stars expected…

太阳与恒星天体物理 · 物理学 2012-06-28 A. J. Korn

A five-dimensional interpolation method and corresponding computer program are developed for using published calculations to determine the non-LTE correction {\Delta\}NLTE to the lithium abundance log{\epsilon}(Li) derived from the Li I…

太阳与恒星天体物理 · 物理学 2017-10-18 L. S. Lyubimkov , D. V. Petrov

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…

太阳与恒星天体物理 · 物理学 2015-05-30 L. Monaco , S. Villanova , P. Bonifacio , E. Caffau , D. Geisler , G. Marconi , Y. Momany , H. -G. Ludwig