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相关论文: A Simultaneous Solution to the ^6Li and ^7Li Big B…

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The $^6$Li abundance observed in metal poor halo stars appears to exhibit a plateau as a function of metallicity similar to that for $^7$Li, suggesting a big bang origin. However, the inferred primordial abundance of $^6$Li is $\sim$1000…

天体物理学 · 物理学 2013-03-21 Motohiko Kusakabe , Toshitaka Kajino , Richard N. Boyd , Takashi Yoshida , Grant J. Mathews

Recent spectroscopic observations of metal poor stars have indicated that both $^7$Li and $^6$Li have abundance plateaus with respect to the metallicity. Abundances of $^7$Li are about a factor three lower than the primordial abundance…

天体物理学 · 物理学 2009-11-11 Motohiko Kusakabe , Toshitaka Kajino , Grant J. Mathews

The primordial Lithium Problem is intimately connected to the assumption that ${}^{7}{\rm Li}$ observed in metal-poor halo stars retains its primordial abundance, which lies significantly below the predictions of standard big-bang…

星系天体物理 · 物理学 2022-04-08 Brian D. Fields , Keith A. Olive

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

Very high-quality spectra of 24 metal-poor halo dwarfs and subgiants have been acquired with ESO's VLT/UVES for the purpose of determining Li isotopic abundances. The derived 1D, non-LTE 7Li abundances from the LiI 670.8nm line reveal a…

天体物理学 · 物理学 2008-11-26 Martin Asplund , David L. Lambert , Poul Erik Nissen , Francesca Primas , Verne V. Smith

The primordial abundances of Deuterium, he4, and li7 are crucial to determination of the baryon density of the Universe in the framework of standard Big Bang nucleosynthesis (BBN). li6 which is only produced in tiny quantities and it is…

We examine the possibility that Big Bang Nucleosynthesis (BBN) may produce non-trivial amounts of $^6$Li. If a primordial component of this isotope could be observed, it would provide a new fundamental test of Big-Bang cosmology, as well as…

天体物理学 · 物理学 2008-11-26 Kenneth M. Nollett , Martin Lemoine , David N. Schramm

The $^7$Li abundance calculated in BBN with the baryon-to-photon ratio fixed from fits to the CMB power spectrum is inconsistent with the observed lithium abundances on the surface of metal-poor halo stars. Previous cosmological solutions…

宇宙学与河外天体物理 · 物理学 2014-07-03 Dai G. Yamazaki , Motohiko Kusakabe , Toshitaka Kajino , Grant. J. Mathews , Myung-Ki Cheoun

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

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 nuclei of the lithium isotopes are fragile, easily destroyed, so that, at variance with most of the other elements, they cannot be formed in stars through steady hydrostatic nucleosynthesis. The 7Li isotope is synthesized during…

星系天体物理 · 物理学 2015-05-18 Monique Spite , François Spite

There exists a well known problem with the Li7+Be7 abundance predicted by standard big bang nucleosynthesis being larger than the value observed in population II stars. The catalysis of big bang nucleosynthesis by metastable, \tau_X \ge…

高能物理 - 唯象学 · 物理学 2008-11-26 Chris Bird , Kristen Koopmans , Maxim Pospelov

Assuming the best numerical value for the cosmic baryonic density and the existence of three neutrino flavors, standard big bang nucleosynthesis is a parameter-free model. It is important to assess if the observed primordial abundances can…

宇宙学与河外天体物理 · 物理学 2020-10-07 Christian Iliadis , Alain Coc

I consider the synthesis of 6Li due to the decay of relic particles, such as gravitinos or moduli, after the epoch of Big Bang Nucleosynthesis. The synthesized 6Li/H ratio may be compared to 6Li/H in metal-poor stars which, in the absence…

天体物理学 · 物理学 2009-10-31 K. Jedamzik

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

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

In the primordial Big Bang nucleosynthesis (BBN), only the lightest nuclides (D, $^3$He, $^4$He, and $^7$Li) were synthesized in appreciable quantities, and these relics provide us a unique window on the early universe. Currently, BBN…

宇宙学与河外天体物理 · 物理学 2014-12-23 J. J. He , S. Q. Hou , A. Parikh , D. Kahl , C. A. Bertulani , other collaborators

We review important reactions in the big bang nucleosynthesis (BBN) model involving a long-lived negatively charged massive particle, $X^-$, which is much heavier than nucleons. This model can explain the observed $^7$Li abundances of…

宇宙学与河外天体物理 · 物理学 2017-09-20 Motohiko Kusakabe , Grant. J. Mathews , Toshitaka Kajino , Myung-Ki Cheoun

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 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
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