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Related papers: New results in primordial nucleosynthesis

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We study effects of long-lived massive particles, which decay during the big-bang nucleosynthesis (BBN) epoch, on the primordial abundances of light elements. Compared to the previous studies, (i) the reaction rates of the standard BBN…

High Energy Physics - Phenomenology · Physics 2018-12-04 Masahiro Kawasaki , Kazunori Kohri , Takeo Moroi , Yoshitaro Takaesu

We take a fresh look at the limits on the number of neutrino flavors derived from big bang nucleosynthesis. In particular, recent measurements of the \he4 abundance enable one to estimate the primordial \he4 mass fraction at $Y_p = 0.232…

High Energy Physics - Phenomenology · Physics 2016-09-01 Keith A. Olive , Gary 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

Nuclear reaction rates are among the most important input for understanding the primordial nucleosynthesis and therefore for a quantitative description of the early Universe. An up-to-date compilation of direct cross sections of 2H(d,p)3H,…

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

Primordial nucleosynthesis provides a probe of the Universe during its early evolution. Given the progress exploring the constituents, structure, and recent evolution of the Universe, it is timely to review the status of Big Bang…

Astrophysics · Physics 2009-06-23 Gary Steigman

Following a brief introduction to early Universe cosmology, the current of status of big bang nucleosynthesis is reviewed and the concordance between theory and observation is examined in detail. The abundances of He4 and Li7 determine the…

Astrophysics · Physics 2007-05-23 Keith A. Olive

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…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-17 S. Q. Hou , J. J. He , A. Parikh , D. Kahl , C. A. Bertulani , T. Kajino , G. J. Mathews , G. Zhao

We have studied the proton-capture reaction 3H(p,{\gamma})4He. It plays a role in the nucleosynthesis of primordial elements in the early Universe leading to the pre-stellar formation of 4He nuclei. All results of our researches and more…

Nuclear Theory · Physics 2019-05-29 Sergey Dubovichenko , Albert Dzhazairov-Kakhramanov , Nataliya Burkova

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

Recent observational and theoretical developments concerning the primordial synthesis of the light elements are reviewed, and the implications for dark matter mentioned.

Astrophysics · Physics 2007-05-23 Subir Sarkar

The ability to now make measurements of Be and B as well as put constraints on \lisix\ abundances in metal-poor stars has led to a detailed reexamination of Big Bang Nucleosynthesis in the $A\groughly6$ regime. The nuclear reaction network…

Astrophysics · Physics 2009-09-15 David Thomas , David N. Schramm , Keith A. Olive , Brian D. Fields

We consider inhomogeneous big bang nucleosynthesis in light of the present observational situation. Different observations of He-4 and D disagree with each other, and depending on which set of observations one uses, the estimated primordial…

Astrophysics · Physics 2009-10-30 K. Kainulainen , H. Kurki-Suonio , E. Sihvola

Based on a scenario of the inhomogeneous big-bang nucleosynthesis (IBBN), we investigate the detailed nucleosynthesis that includes the production of heavy elements beyond Li-7. From the observational constraints on light elements of He4…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-08 Riou Nakamura , Masa-aki Hashimoto , Shin-ichiro Fujimoto , Nobuya Nishimura , Katsuhiko Sato

The simplest, `standard' model of Big Bang Nucleosynthesis (SBBN) assumes three light neutrinos (N_nu = 3) and no significant electron neutrino asymmetry, leaving only one adjustable parameter: the baryon to photon ratio eta. The primordial…

Astrophysics · Physics 2009-11-10 James P. Kneller , Gary Steigman

We investigate the possibility that inhomogeneous nucleosynthesis may eventually be used to explain the abundances of \li6, \be9 and B in population II stars. The present work differs from previous studies in that we have used a more…

We reinvestigate effects of neutrino oscillations on the production of 7Li and 11B in core-collapse supernovae (SNe). During the propagation of neutrinos from the proto-neutron star, their flavors change and the neutrino reaction rates for…

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…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Brian D. Fields , Paolo Molaro , Subir Sarkar

In the standard Big-Bang nucleosynthesis (BBN) model, the primordial $^7$Li abundance is overestimated by about a factor of 2--3 comparing to the astronomical observations, so called the pending cosmological lithium problem. The…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 S. Q. Hou , J. J. He , S. Kubono , Y. S. Chen

We consider the effect on Big Bang Nucleosynthesis (BBN) of new measurements of the $d(p,\gamma){}^3$He cross section by the LUNA Collaboration. These have an important effect on the primordial abundance of D/H which is also sensitive to…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-23 Tsung-Han Yeh , Keith A. Olive , Brian D. Fields
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