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We have measured the Li abundance of 18 stars with -2 <~ [Fe/H] ~< -1 and 6000 K <~ Teff <~ 6400 K, a parameter range that was poorly represented in previous studies. We examine the Galactic chemical evolution (GCE) of this element,…

Since 7Li is easily destroyed in low temperatures, the surface lithium abundance decreases as stars evolve. This is supported by the lithium depletion observed in the atmosphere of most red giants. However, recent studies show that almost…

太阳与恒星天体物理 · 物理学 2021-03-17 Kanji Mori , Motohiko Kusakabe , A. Baha Balantekin , Toshitaka Kajino , Michael A. Famiano

The light element lithium is formed by nucleosynthesis during the Big Bang. Its abundance can help to define the parameters of the early universe. To find this primordial value, it is necessary to determine Li abundances in the oldest stars…

太阳与恒星天体物理 · 物理学 2023-07-28 Ann Merchant Boesgaard , Constantine P. Deliyannis

We review the Galactic chemical evolution of Li6 and compare these results with recent observational determinations of the lithium isotopic ratio. In particular, we concentrate on so-called standard Galactic cosmic-ray nucleosynthesis in…

天体物理学 · 物理学 2009-10-31 Brian D. Fields , Keith A. Olive

Context: Lithium is a fragile element, which is easily destroyed in the stellar interior. The existence of lithium-rich giants still represents a challenge for stellar evolution models. Aims: We have collected a large database of…

太阳与恒星天体物理 · 物理学 2015-05-27 L. Monaco , S. Villanova , C. Moni Bidin , G. Carraro , D. Geisler , P. Bonifacio , O. A. Gonzalez , M. Zoccali , L. Jilkova

The discrepancy between the predictions of primordial nucleosynthesis and the observed lithium abundance in Spite plateau stars has been attributed either to a challenge to the standard model of nucleosynthesis or to stellar processes…

宇宙学与河外天体物理 · 物理学 2025-10-17 Oswaldo D. Miranda

This is a report on some highlights of some research on the rare light elements, lithium (Li), beryllium (Be), and boron (B), that I presented in my Henry Norris Russell Lecture in January, 2020. It is not a comprehensive review of work on…

太阳与恒星天体物理 · 物理学 2023-02-01 Ann Merchant Boesgaard

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

We present a survey of lithium abundances in 185 main- sequence field stars with Teff between 5600 and 6600 K and [Fe/H] from -1.4 to +0.2 based on high-resolution spectra of 130 stars and a reanalysis of data from Lambert et al. (1991).…

天体物理学 · 物理学 2009-11-06 Y. Q. Chen , P. E. Nissen , T. Benoni , G. Zhao

We point out that the cosmological abundance of ${}^7$Li can be reduced down to observed values if during its formation Big Bang Nucleosynthesis is modified by the presence of light electrically neutral particles $X$ that have substantial…

高能物理 - 唯象学 · 物理学 2016-06-01 Andreas Goudelis , Maxim Pospelov , Josef Pradler

The possibility that the so-called "lithium problem", i.e. the disagreement between the theoretical abundance predicted for primordial $^7$Li assuming standard nucleosynthesis and the value inferred from astrophysical measurements, can be…

宇宙学与河外天体物理 · 物理学 2016-11-03 Laura Salvati , Luca Pagano , Massimiliano Lattanzi , Martina Gerbino , Alessandro Melchiorri

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

We review the main sources of LiBeB production and show that a primary mechanism is at work in the early Galaxy involving both ejection and acceleration of He, C and O at moderate energy, which by nuclear interaction with H and He produce…

天体物理学 · 物理学 2016-11-03 M. Casse , E. Vangioni-Flam , J. Audouze

High lithium-7 ($\mathrm{^7Li}$) abundances in giants are indicative of non-standard physical processes affecting the star. Mechanisms that could produce this signature include contamination from an external source, such as planets, or…

太阳与恒星天体物理 · 物理学 2020-07-15 Claudia Aguilera-Gómez , Julio Chanamé , Marc H. Pinsonneault

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

The production of the stable isotope Li-6 in standard Big Bang nucleosynthesis has recently attracted much interest. Recent observations in metal-poor stars suggest that a cosmological Li-6 plateau may exist. If true, this plateau would…

Accurate 7Li(d,n)24He thermonuclear reaction rates are crucial for precise prediction of the primordial abundances of Lithium and Beryllium and to probe the mysteries beyond fundamental physics and the standard cosmological model. However,…

宇宙学与河外天体物理 · 物理学 2021-11-03 S. Q. Hou , T. Kajino , T. C. L. Trueman , M. Pignatari , Y. D. Luo , C. A. Bertulani

I review measurements of the most important reactions involved in the creation and destruction of Li and Be during big bang nucleosynthesis (BBN) as well as their uncertainties and the relative contributions they make to the uncertainty in…

宇宙学与河外天体物理 · 物理学 2020-02-14 Barry Davids

We report the serendipitous discovery of a very metal-poor (VMP) Li-rich giant star ($T_{\rm eff}$ = 4690$\pm$80 K, log g = 1.34$\pm$0.13, [Fe/H] = $-2.43\pm$0.07). We analyse the Li I 6103 and 6707 \r{A} lines accounting for departures…

星系天体物理 · 物理学 2023-10-30 T. M. Sitnova , T. Matsuno , Z. Yuan , N. F. Martin , P. Banerjee , F. Sestito , K. A. Venn , J. I. González Hernández

According to standard models supernovae produce radioactive $^{44}$Ti, which should be visible in gamma-rays following decay to $^{44}$Ca for a few centuries. $^{44}Ti production is believed to be the source of cosmic $^{44}$Ca, whose…