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Related papers: The X^- Solution to the ^6Li and ^7Li Big Bang Nuc…

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Recently it is reported that there is the discrepancy between big bang nucleosynthesis theory and observations (BBN crisis). We show that BBN predictions agree with the primordial abundances of light elements, He4, D, He3 and Li7 inferred…

Astrophysics · Physics 2008-11-26 K. Kohri , M. Kawasaki , Katsuhiko Sato

The early, hot, dense, expanding Universe was a primordial reactor in which the light nuclides D, 3He, 4He and 7Li were synthesized in astrophysically interesting abundances. The challenge to the standard hot big bang model (Big Bang…

Astrophysics · Physics 2007-05-23 Gary Steigman

Since the pioneering observations of Spite & Spite in 1982, the constant lithium abundance of metal-poor ([Fe/H]<-1.3) halo stars near the turnoff has been attributed a cosmological origin. Closer analysis revealed that the observed…

Astrophysics · Physics 2008-11-26 L. Piau , T. C. Beers , D. S. Balsara , T. Sivarani , J. W. Truran , J. W. Ferguson

A change in the fundamental constants of nature or plasma effects in the early universe could stabilize $^8$Be against decay into two $^4$He nuclei. Coc et al. examined this effect on big bang nucleosynthesis as a function of $B_8$, the…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-11 Richard T. Scherrer , Robert J. Scherrer

We present a detailed study of inhomogeneous Big Bang nucleosynthesis where, for the first time, nuclear reactions are coupled to all significant fluctuation dissipation processes. Theses processes include neutrino heat transport, baryon…

Astrophysics · Physics 2009-10-22 K. Jedamzik , G. M. Fuller , G. 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

During its hot, dense, early evolution the Universe was a primordial nuclear reactor, synthesizing the light nuclides D, 3He, 4He and 7Li in the first thousand seconds. The presently observed abundances of these relic nuclides provide a…

Astrophysics · Physics 2007-05-23 G. Steigman

We derive constraints from standard (with $N_\nu = 3$) BBN arising solely from two cosmologically produced nuclides, \he4 and \li7, from which the extrapolation to primordial abundances is straightforward. The abundances of D and \he3 are…

High Energy Physics - Phenomenology · Physics 2009-09-15 Brian D. Fields , Keith A. Olive

The predictions of Standard Big Bang Nucleosynthesis are summarized and compared with observations of abundances of helium in HII regions, deuterium in quasar absorbers, deuterium and helium-3 in the Galaxy, and lithium in metal-poor stars.…

Astrophysics · Physics 2007-05-23 Craig J. Hogan

We compute the big bang nucleosynthesis limit on the number of light neutrino degrees of freedom in a model-independent likelihood analysis based on the abundances of He4 and Li7. We use the two-dimensional likelihood functions to…

High Energy Physics - Phenomenology · Physics 2008-11-26 Keith A. Olive , David Thomas

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

During big bang nucleosynthesis, any injection of extra neutrons around the time of the $^7$Be formation, i.e. at a temperature of order $T \simeq 50$~keV, can reduce the predicted freeze-out amount of $^7$Be + $^7$Li that otherwise remains…

High Energy Physics - Phenomenology · Physics 2014-10-29 Alain Coc , Maxim Pospelov , Jean-Philippe Uzan , Elisabeth Vangioni

A scenario of the Big-Bang Nucleosynthesis is analyzed within the Minimal Supersymmetric Standard Model which is consistent with a stau-neutralino coannihilation scenario to explain the relic abundance of dark matter. We find that we can…

High Energy Physics - Phenomenology · Physics 2009-11-13 Toshifumi Jittoh , Kazunori Kohri , Masafumi Koike , Joe Sato , Takashi Shimomura , Masato Yamanaka

Charged massive particles (CHAMPs), when present during the Big Bang nucleosynthesis (BBN) era, may significantly alter the synthesis of light elements when compared to a standard BBN scenario. This is due to the formation of bound states…

Astrophysics · Physics 2008-12-18 Karsten Jedamzik

WThe current status of big bang nucleosynthesis is reviewed with an emphasis on the comparison between the observational determination of the light element abundances of \D, \he3, \he4 and \li7 and the predictions from theory. In…

Astrophysics · Physics 2009-09-15 Keith A. Olive , Sean T. Scully

We show that primordial nucleosynthesis in baryon inhomogeneous big-bang models can lead to significant heavy-element production while still satisfying all the light-element abundance constraints including the low lithium abundance observed…

Astrophysics · Physics 2009-10-22 K. Jedamzik , G. M. Fuller , G. J. Mathews , T. Kajino

We examine the Big Bang nucleosynthesis (BBN) process in the presence of small-scale baryon inhomogeneities. Primordial abundance yields for D, He4, Li6, Li7, Be9, and B11 are computed for wide ranges of parameters characterizing the…

Astrophysics · Physics 2009-11-06 K. Jedamzik , Jan B. Rehm

Lithium abundance derived in metal-poor main sequence stars is about three times lower than the value of primordial Li predicted by the standard Big Bang nucleosynthesis when the baryon density is taken from the CMB or the deuterium…

Solar and Stellar Astrophysics · Physics 2015-06-22 Xiaoting Fu , Alessandro Bressan , Paolo Molaro , Paola Marigo

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 2007-05-23 Brian Fields , Subir Sarkar

We have refined the estimate of the primordial level of $^7$Li abundance to an accuracy better than 10%, based on high-precision Li abundances for metal-poor halo stars, and a recent model of post-BBN (Big Bang Nucleosynthesis) chemical…

Astrophysics · Physics 2009-10-31 Takeru Ken Suzuki , Yuzuru Yoshii , Timothy C. Beers
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