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Related papers: Dynamical Screening Effects on Big Bang Nucleosynt…

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We examine big bang nucleosynthesis (BBN) in models with a time-varying gravitational constant $G$, when this time variation is rapid on the scale of the expansion rate $H$, i.e, $\dot G/G \gg H$. Such models can arise naturally in the…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-19 Anish Giri , Robert J. Scherrer

Big-bang nucleosynthesis (BBN) describes the production of the lightest nuclides via a dynamic interplay among the four fundamental forces during the first seconds of cosmic time. We briefly overview the essentials of this physics, and…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-13 Richard H. Cyburt , Brian D. Fields , Keith A. Olive , Tsung-Han Yeh

Thermonuclear fusion reaction rates in the solar plasma are enhanced by the presence of the electron cloud that screens fusing nuclei. The present work studies the influence of electron screening deformations on solar reaction rates in the…

Nuclear Theory · Physics 2009-11-06 Theodore E. Liolios

Big Bang Nucleosynthesis provides us with an observational insight into the very early Universe. Since this mechanism of light element synthesis comes out of the standard model of particle cosmology which follows directly from General…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-14 Sai Swagat Mishra , Ameya Kolhatkar , P. K. Sahoo

Current precision big bang nucleosynthesis (BBN) studies motivate us to revisit the neutron lifespan in the plasma medium of the early universe. The mechanism we explore is the Fermi-blocking of decay electrons and neutrinos by plasma. As…

Nuclear Theory · Physics 2018-05-18 Cheng Tao Yang , Jeremiah Birrell , Johann Rafelski

As the early universe expands and cools the rates of the weak interactions that keep neutrinos in thermal equilibrium with the matter and the related rates of the reactions that inter-convert neutrons and protons decrease. Eventually, these…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-31 Evan Grohs , George M. Fuller

We study the role of the effective Coulomb interaction strength and length on the dynamics of nucleons in conditions according to those in a neutron star's crust. Calculations were made with a semi-classical molecular dynamics model,…

Nuclear Theory · Physics 2014-05-14 P. N. Alcain , P. A. Giménez Molinelli , J. I. Nichols , C. O. Dorso

Primordial nucleosynthesis is considered a success story of the standard big bang (SBB) cosmology. The cosmological and elementary particle physics parameters are believed to be severely constrained by the requirement of correct abundances…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Daksh Lohiya , Annu Batra , Shobhit Mahajan , Amitabha Mukherjee

The weak interaction charged current processes ($\nu_e+n\leftrightarrow p+e^-$, $\bar\nu_e +p\leftrightarrow n+e^+$, $n\leftrightarrow p+e^-+\bar\nu_e$) interconvert neutrons and protons in the early universe and have significant influence…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-07 E. Grohs , G. M. Fuller

A reliable description of nuclear fusion reactions in inner layers of white dwarfs and envelopes of neutron stars is important for realistic modelling of a wide range of observable astrophysical phenomena from accreting neutron stars to…

High Energy Astrophysical Phenomena · Physics 2021-09-29 D. A. Baiko

This paper presents a detailed study of the electron degeneracy and nonlinear screening effects which play a crucial role in the validity of Salpeter's weak-screening model. The limitations of that model are investigated and an improved one…

Nuclear Theory · Physics 2009-09-29 Theodore E. Liolios

We investigate the impact of big bang nucleosynthesis (BBN) on the Hubble tension, focusing on how the treatment of the reaction rate and observational data affect the evaluation of the tension. We show that the significance of the tension…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-02 Tomo Takahashi , Yo Toda

We seek to understand the effect of high electron density in the proximity of a heavy nucleus on the fusion reaction rates in a hot plasma phase. We investigate quantitatively the catalytic effect of gold ($Z=79$) ions embedded in an…

Plasma Physics · Physics 2025-12-23 Christopher Grayson , Johann Rafelski

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

The fluctuation-dissipation theorem is used to evaluate the screening factor of nuclear reactions due to the electromagnetic fluctuations in a plasma. We show that the commonly used Saltpeter factor is obtained if only fluctuations near the…

Astrophysics · Physics 2007-05-23 Merav Opher , Reuven Opher

Big Bang Nucleosynthesis (BBN), as one of the earliest processes in the universe accessible to direct observation, offers a powerful and independent probe of the cosmic expansion history. With recent advances in both theory and observation,…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-25 Christopher Cook , Joel Meyers

We analyze the effect of plasma screening on nuclear reaction rates in dense matter composed of atomic nuclei of one or two types. We perform semiclassical calculations of the Coulomb barrier penetrability taking into account a radial mean…

Solar and Stellar Astrophysics · Physics 2009-08-20 A. I. Chugunov , H. E. De Witt

If highly efficient, cosmic ray production can have a significant effect on the X-ray emission from SNRs as well as their dynamical evolution. Using hydrodynamical simulations including diffusive shock acceleration, we produce spectra for…

The present paper completes a series of our works on non-thermal nuclear processes in big bang nucleosynthesis (BBN) started in JCAP05(2008)010 (Part I) and 05(2009)001 (Part II). The processes are triggered by non-Maxwellian particles…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-20 Victor T. Voronchev

We consider the implications of the modified dispersion relations, due to the noncommutativity of the spacetime, for a photon gas filling the early Universe in the framework of the Big Bang Nucleosynthesis (BBN) processes, during the period…

General Relativity and Quantum Cosmology · Physics 2026-04-28 Teodora Maria Matei , Cristian Croitoru , Tiberiu Harko