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Related papers: Possible solution to the $^7$Li problem by the lon…

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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…

Solar and Stellar Astrophysics · Physics 2020-07-15 Claudia Aguilera-Gómez , Julio Chanamé , Marc H. Pinsonneault

A critical review is given of the current status of cosmological nucleosynthesis. In the framework of the Standard Model with 3 types of relativistic neutrinos, the baryon-to-photon ratio, $\eta$, corresponding to the inferred primordial…

Astrophysics · Physics 2011-02-09 Brian Fields , Subir Sarkar

We consider the effects of the injections of energetic photon and electron (or positron) on the big-bang nucleosynthesis. We study the photodissociation of light elements in the early Universe paying particular attention to the case that…

High Energy Physics - Phenomenology · Physics 2021-01-06 Masahiro Kawasaki , Kazunori Kohri , Takeo Moroi , Kai Murai , Hitoshi Murayama

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 extensively reanalyze effects of a long-lived negatively charged massive particle, X-, on big bang nucleosynthesis (BBN). The BBN model with an X- particle was originally motivated by the discrepancy between 6,7Li abundances predicted in…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Motohiko Kusakabe , K. S. Kim , Myung-Ki Cheoun , Toshitaka Kajino , Yasushi Kino , Grant. J. Mathews

A large number of stellar evolution models with [Fe/H] = -2.3 and -3.3 have been calculated in order to determine the primordial $^7$Li abundance and to test current stellar evolution models by a comparison to the extensive database of Li…

Astrophysics · Physics 2009-10-22 Brian Chaboyer , P. Demarque

Recent determinations of the deuterium abundance, $^2$H/H, in high redshift Lyman limit hydrogen clouds challenge the usual picture of primordial nucleosynthesis based on \lq\lq concordance\rq\rq\ of the calculated light element ($^2$H,…

Astrophysics · Physics 2009-10-28 George M. Fuller , Christian Y. Cardall

We studied previously the impact on light-element abundances of gravitinos decaying during or after Big-Bang nucleosynthesis (BBN). We found regions of the gravitino mass m_{3/2} and abundance zeta_{3/2} plane where its decays could…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Richard H. Cyburt , John Ellis , Brian D. Fields , Feng Luo , Keith A. Olive , Vassilis C. Spanos

The decays of massive gravitinos into neutralino dark matter particles and Standard Model secondaries during or after Big-Bang nucleosynthesis (BBN) may alter the primordial light-element abundances. We present here details of a new suite…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-08 Richard H. Cyburt , John Ellis , Brian D. Fields , Feng Luo , Keith A. Olive , Vassilis C. Spanos

Recently we presented a simple method for determining the correlated uncertainties of the light element abundances expected from big bang nucleosynthesis, which avoids the need for lengthy Monte Carlo simulations. We now extend this…

High Energy Physics - Phenomenology · Physics 2008-11-26 E. Lisi , Subir Sarkar , F. L. Villante

An accurate quantum three-body calculation is performed for the new type of big-bang nucleosynthesis (BBN) reactions that are catalyzed by a long-lived negatively-charged, massive leptonic particle (called X^-) such as the supersymmetric…

Nuclear Theory · Physics 2009-08-11 Masayasu Kamimura , Yasushi Kino , Emiko Hiyama

We study the temporal evolution of the 7Li abundance in the gaseous medium for all the components (halo, disk and bulge) of our Galaxy. We adopt nucleosynthesis prescriptions on stellar lithium production based upon recent observational…

Astrophysics · Physics 2016-08-30 Donatella Romano

We consider scenarios in which the lightest sparticle (LSP) is the gravitino and the next-to-lightest sparticle (NLSP) is a metastable stau. We examine the production of stau pairs in e^{+}e^{-} annihilation at ILC and CLIC energies. In…

High Energy Physics - Phenomenology · Physics 2008-03-18 Orhan Cakir , Ilkay T. Cakir , John R. Ellis , Zerrin Kirca

We consider constraints on long-lived charged scalar leptons \tilde{l}^\pm in supersymmetric models, where gravitino is the lightest superparticle. We study the decay and hadronization processes of \tilde{l}^\pm. We also take into account…

High Energy Physics - Phenomenology · Physics 2008-11-26 Masahiro Kawasaki , Kazunori Kohri , Takeo Moroi

Catalysis of nuclear reactions by metastable charged particles X^- opens the possibility for primordial production of elements with A>7. We calculate the abundance of ^9Be, where synthesis is mediated by the formation of (^8Be X^-) bound…

High Energy Physics - Phenomenology · Physics 2007-12-06 Maxim Pospelov

Motivated by the recent measurement of the primeval abundance of deuterium, we re-examine the nuclear inputs to big-bang nucleosynthesis (BBN). Using Monte-Carlo realization of the nuclear cross-section data to directly estimate the…

Astrophysics · Physics 2009-10-31 Scott Burles , Kenneth M. Nollett , James N. Truran , Michael S. Turner

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…

Primordial nucleosynthesis, or big bang nucleosynthesis (BBN), is one of the three evidences for the big bang model, together with the expansion of the universe and the cosmic microwave background. There is a good global agreement over a…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-20 Alain Coc , Elisabeth Vangioni

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…

Solar and Stellar Astrophysics · Physics 2020-04-17 S. Cassisi , M. Salaris , S. Degl'Innocenti , P. G. Prada Moroni , E. Tognelli

A possible resolution of the $^7$Li problem within the Standard Model Big-Bang Nucleosynthesis is presented. The key idea originates from the application of the Scale-Invariant Vacuum (SIV) paradigm to the BBN. However, here we arrive at…

Nuclear Theory · Physics 2025-10-01 Vesselin G. Gueorguiev
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