中文
相关论文

相关论文: A probable stellar solution to the cosmological li…

200 篇论文

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

A homogeneous spectroscopic analysis of unevolved and evolved stars in the metal-poor globular cluster NGC 6397 with FLAMES-UVES reveals systematic trends of stellar surface abundances that are likely caused by atomic diffusion. This…

天体物理学 · 物理学 2008-11-26 A. J. Korn , F. Grundahl , O. Richard , P. S. Barklem , L. Mashonkina , R. Collet , N. Piskunov , B. Gustafsson

Big-bang nucleosynthesis (BBN) theory, together with the precise WMAP cosmic baryon density, makes tight predictions for the abundances of the lightest elements. Deuterium and 4He measurements agree well with expectations, but 7Li…

宇宙学与河外天体物理 · 物理学 2012-03-19 Brian D. Fields

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

To constrain the universe before recombination (380000 years after the Big Bang), we mostly rely on the measurements of the primordial abundances that indicate the first insight into the thermal history of the universe. The first production…

宇宙学与河外天体物理 · 物理学 2024-04-30 Tahani Makki , Mounib El Eid , Grant Mathews

Thanks to the accurate determination of the baryon density of the universe by the recent cosmic microwave background experiments, updated predictions of the standard model of Big Bang nucleosynthesis now yield the initial abundance of the…

天体物理学 · 物理学 2015-06-24 C. Charbonnel , F. Primas

The primordial abundances of light elements produced in the standard theory of Big Bang nucleosynthesis (BBN) depend only on the cosmic ratio of baryons to photons, a quantity inferred from observations of the microwave background. The…

宇宙学与河外天体物理 · 物理学 2015-03-20 J. Christopher Howk , Nicolas Lehner , Brian D. Fields , Grant J. Mathews

I summarize the stellar side of the cosmological lithium problem(s). Evidence from independent studies is accumulating and indicates that stars may very well be fully responsible for lowering their surface lithium from the predicted…

太阳与恒星天体物理 · 物理学 2024-06-17 A. J. Korn

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 standard model of primordial nucleosynthesis by the Big Bang as selected by the WMAP-based estimate of the baryon density ($\Omega_bh^2$) predicts an abundance of $^7$Li that is a factor of three greater than the generally reported…

天体物理学 · 物理学 2009-11-10 David L. Lambert

Big Bang nucleosynthesis (BBN) theory predicts the abundances of the light elements D, $^3$He, $^4$He and $^7$Li produced in the early universe. The primordial abundances of D and $^4$He inferred from observational data are in good…

宇宙学与河外天体物理 · 物理学 2017-01-17 S. Q. Hou , J. J. He , A. Parikh , D. Kahl , C. A. Bertulani , T. Kajino , G. J. Mathews , G. Zhao

The cosmological lithium problem, i.e. the discrepancy between the lithium abundance predicted by the Big Bang Nucleosynthesis and the one observed for the stars of the "Spite plateau", is one of the long standing problems of modern…

太阳与恒星天体物理 · 物理学 2020-04-17 S. Cassisi , M. Salaris , S. Degl'Innocenti , P. G. Prada Moroni , E. Tognelli

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

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 cosmological lithium problem -- that theory predicts a primordial abundance far higher than the observed value -- has resisted decades of attempts by cosmologists, nuclear physicists, and astronomers alike to root out systematics. We…

高能物理 - 唯象学 · 物理学 2023-09-21 Seth Koren

Combined with other CMB experiments, the WMAP survey provides an accurate estimate of the baryon density of the Universe. In the framework of the standard Big Bang Nucleosynthesis (BBN), such a baryon density leads to predictions for the…

天体物理学 · 物理学 2009-01-19 Julien Larena , Jean-Michel Alimi , Arturo Serna

One of the three testaments in favor of the big bang theory is the prediction of the primordial elemental abundances in the big-bang nucleosynthesis (BBN). The Standard BBN is a parameter-free theory due to the precise knowledge of the…

核理论 · 物理学 2024-05-28 Vinay Singh , Debasis Bhowmick , D. N. Basu

We make use of high resolution, high signal-to-noise ratio spectra of 12 turn-off stars in the metal-poor globular cluster NGC 6397 to measure its lithium content. We conclude that they all have the same lithium abundance A(Li) = 2.34 with…

Standard big bang nucleosynthesis (BBNS) promises accurate predictions of the primordial abundances of deuterium, helium-3, helium-4 and lithium-7 as a function of a single parameter. Previous measurements have nearly always been…

天体物理学 · 物理学 2008-02-03 Scott Burles , David Tytler

The prediction of the PLANCK-constrained primordial lithium abundance in the Universe is in discordance with the observed Li abundances in warm Population II dwarf and subgiant stars. Among the physically best motivated ideas, it has been…

‹ 上一页 1 2 3 10 下一页 ›