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For a brief time in its early evolution the Universe was a cosmic nuclear reactor. The expansion and cooling of the Universe limited this epoch to the first few minutes, allowing time for the synthesis in astrophysically interesting…

宇宙学与河外天体物理 · 物理学 2010-09-27 Gary Steigman

The theoretical predictions of big bang nucleosynthesis (BBN) are dominated by uncertainties in the input nuclear reaction cross sections. In this paper, we examine the impact on BBN of the recent compilation of nuclear data and…

天体物理学 · 物理学 2009-09-15 Richard H. Cyburt , Brian D. Fields , Keith A. Olive

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 identify reactions which destroy 7Be and 7Li during big bang nucleosynthesis (BBN) in the scenario of BBN catalyzed by a long-lived sub-strongly interacting massive particle (sub-SIMP or X particle). The destruction associated with non…

高能物理 - 唯象学 · 物理学 2011-03-22 Masahiro Kawasaki , Motohiko Kusakabe

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…

天体物理学 · 物理学 2009-09-15 David Thomas , David N. Schramm , Keith A. Olive , Brian D. Fields

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…

天体物理学 · 物理学 2009-10-31 Scott Burles , Kenneth M. Nollett , James N. Truran , Michael S. Turner

In this study we present a comprehensive sensitivity atlas for Big Bang Nucleosynthesis (BBN) in which we quantify the dependence of the primordial abundances of helium-4, deuterium, and lithium-7 as well as $N_{\rm{eff}}$ on variations in…

高能物理 - 唯象学 · 物理学 2026-03-25 Anne-Katherine Burns

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

We report the results of a new accurate evaluation of light nuclei yields in primordial nucleosynthesis. All radiative effects, finite nucleon mass, thermal and plasma corrections are included in the proton to neutron conversion rates. The…

天体物理学 · 物理学 2008-11-26 S. Esposito , G. Mangano , G. Miele , O. Pisanti

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…

高能物理 - 唯象学 · 物理学 2009-09-15 Brian D. Fields , 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…

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

In a recent Letter entitled "Measurement of d + 7Be Cross Sections for Big-Bang Nucleosynthesis", Rijal et al. describe the results of an experiment that put the d + 7Be reaction rate on firmer ground. The erratum of Rijal et al. claims…

宇宙学与河外天体物理 · 物理学 2019-12-12 Alain Coc , Barry Davids

The injections of energetic hadrons could have occurred in the early universe by decays of hypothetical long-lived exotic particles. The injections induce the showers of nonthermal hadrons via nuclear scattering. Neutrons generated at these…

宇宙学与河外天体物理 · 物理学 2014-08-13 Motohiko Kusakabe , Myung-Ki Cheoun , K. S. Kim

Primordial or big bang nucleosynthesis (BBN) is one of the three historical strong evidences for the big bang model. The recent results by the Planck satellite mission have slightly changed the estimate of the baryonic density compared to…

宇宙学与河外天体物理 · 物理学 2015-06-19 Alain Coc , Jean-Philippe Uzan , Elisabeth Vangioni

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…

宇宙学与河外天体物理 · 物理学 2017-10-11 Richard T. Scherrer , Robert J. Scherrer

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

We consider Big Bang Nucleosynthesis (BBN) with long lived charged massive particles. Before decaying, the long lived charged particle recombines with a light element to form a bound state like a hydrogen atom. This effect modifies the…

高能物理 - 唯象学 · 物理学 2008-11-26 Kazunori Kohri , Fumihiro Takayama

Of the light nuclides observed in the universe today, D, 3He, 4He, and 7Li are relics from its early evolution. The primordial abundances of these relics, produced via Big Bang Nucleosynthesis (BBN) during the first half hour of the…

天体物理学 · 物理学 2007-05-23 Gary Steigman

The reaction rates of the direct astrophysical capture processes $^{3}{\rm He}(\alpha, \gamma)^{7}{\rm Be}$ and $^{3}{\rm H}(\alpha,\gamma)^{7}{\rm Li}$, as well as the abundance of the $^{7}{\rm Li}$ element are estimated in the framework…

核理论 · 物理学 2019-08-06 S. A. Turakulov , E. M. Tursunov

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