English
Related papers

Related papers: Non-extensive Statistics Solution to the Cosmologi…

200 papers

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…

Astrophysics of Galaxies · Physics 2022-04-08 Brian D. Fields , Keith A. Olive

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

The current of status of big bang nucleosynthesis is reviewed and the concordance between theory and observation is examined in detail. It is argued that when using the observational data on he4 and li7, the two isotopes whose abundances…

Astrophysics · Physics 2008-02-03 Keith A. Olive

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

Big-bang nucleosynthesis is one of the cornerstones of the standard cosmology. For almost thirty years its predictions have been used to test the big-bang model to within a fraction of a second of the bang. The concordance that exists…

Astrophysics · Physics 2009-10-22 Craig J Copi , David N. Schramm , Michael S. Turner

Residual late-time dark matter particle annihilations during and after Big Bang Nucleosynthesis (BBN) may alter the predicted cosmological abundances of the light elements. Within the constrained minimal supersymmetric extension of the…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-29 John Ellis , Brian D. Fields , Feng Luo , Keith A. Olive , Vassilis C. Spanos

We reexamine big bang nucleosynthesis with large-scale baryon density inhomogeneities when the length scale of the density fluctuations exceeds the neutron diffusion length ($\sim 10^7-10^8$ cm at BBN), and the amplitude of the fluctuations…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-12 John D. Barrow , Robert J. Scherrer

We consider the effects on big bang nucleosynthesis (BBN) of the radiative decay of a long-lived massive particle. If high-energy photons are emitted after the BBN epoch ($t \sim 1 - 10^3$ sec), they may change the abundances of the light…

High Energy Physics - Phenomenology · Physics 2011-05-05 M. Kawasaki , K. Kohri , Takeo Moroi

We consider the effects of uncertainties in nuclear reaction rates on the cosmological constraints on the decays of unstable particles during or after Big-Bang nucleosynthesis (BBN). We identify the nuclear reactions due to non-thermal…

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

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 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…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-20 Motohiko Kusakabe , Grant. J. Mathews , Toshitaka Kajino , Myung-Ki Cheoun

After few minutes the Universe evolved through conditions of temperature and density which permitted the first synthesis of astrophysically interesting abundances of D, 3He, 4He and 7Li. The relic abundances are sensitive probes of the…

Astrophysics · Physics 2007-08-30 Paolo Molaro

Inhomogeneous big bang nucleosynthesis (BBN) produces a spatially inhomogeneous distribution of element abundances at $T \sim 10^9$ K, but subsequent element diffusion will tend to erase these inhomogeneities. We calculate the cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-07 Robert J. Scherrer

Big Bang Nucleosynthesis (BBN) explores the first few minutes of nuclei formation after the Big Bang. We present updates that result in new constraints at the 2{\sigma} level for the abundances of the four primary light nuclides -…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-20 Michael Foley , Nishanth Sasankan , Motohiko Kusakabe , Grant. J. Mathews

We explore a nuclear physics resolution to the discrepancy between the predicted standard big-bang nucleosynthesis (BBN) abundance of 7Li and its observational determination in metal-poor stars. The theoretical 7Li abundance is 3-4 times…

Cosmology and Nongalactic Astrophysics · Physics 2011-05-10 Nachiketa Chakraborty , Brian D. Fields , Keith A. Olive

After a brief review of the cosmological lithium problem, we report a few recent attempts to find theoretical solutions by our group at Texas A&M University (Commerce & College Station). We will discuss our studies on the theoretical…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-03 C. A. Bertulani , A. M. Mukhamedzhanov , Shubhchintak

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

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

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

Big bang nucleosynthesis (BBN) and the cosmic microwave background (CMB) have a long history together in the standard cosmology. The general concordance between the predicted and observed light element abundances provides a direct probe of…

Astrophysics · Physics 2009-11-10 Richard H. Cyburt
‹ Prev 1 3 4 5 6 7 10 Next ›