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Related papers: Big Bang nucleosynthesis with a non-Maxwellian dis…

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We extend the model-independent likelihood analysis of big bang nucleosynthesis (BBN) based on He4 and Li7 to allow for numbers of degrees of freedom which differ from the standard model value characterized by $N_\nu = 3$. We use the…

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

We study the effects of the environment described by the Tsallis nonextensive statistics on physical quantities using an optimization method in the case of small deviation from the Boltzmann-Gibbs statistics. The $x^4$ model is used and the…

Statistical Mechanics · Physics 2014-12-23 Masamichi Ishihara

We discuss the possibility of implementing axiomatic nonextensive statistics, where it is conjectured that the phase-space volume determines the (non)extensive entropy, on the particle production at NICA energies. Both Boltzmann-Gibbs and…

Nuclear Theory · Physics 2016-08-23 Abdel Nasser Tawfik

This is a concise introduction to the topic of nonextensive Tsallis statistics meant especially for those interested in its relation to high energy proton-proton, proton-nucleus, and nucleus-nucleus collisions. The three types of Tsallis…

High Energy Physics - Phenomenology · Physics 2021-10-11 Joseph I. Kapusta

The particle production in relativistic heavy-ion collisions seems to be created in a dynamically disordered system which can be best described by an extended exponential entropy. In distinguishing between the applicability of this and…

Nuclear Theory · Physics 2018-05-29 Abdel Nasser Tawfik , Hayam Yassin , Eman R. Abo Elyazeed

We use Big Bang Nucleosynthesis calculations and light element abundance data to constrain the relative variation of the deuteron binding energy since the universe was a few minutes old, $\delta Q = Q(BBN)-Q(present)$. Two approaches are…

Astrophysics · Physics 2009-08-18 V. F. Dmitriev , V. V. Flambaum , J. K. Webb

To describe high energy collisions one widely uses thermodynamical methods and concepts which follow the classical Boltzmann-Gibbs (BG) approach. In many cases, however, either some deviations from the expected behaviour are observed…

High Energy Physics - Phenomenology · Physics 2015-06-25 G. Wilk , Z. Wlodarczyk

We present an improved calculation of the light element abundances in the framework of Big Bang nucleosynthesis as a function of the Higgs vacuum expectation value $v$. We compare the methods of our calculation to previous literature…

High Energy Physics - Phenomenology · Physics 2024-06-18 Helen Meyer , Ulf-G. Meißner

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 investigate how the non-extensive approach works in high-energy physics. Transverse momentum ($p_T$) spectra of several hadrons are fitted by various non-extensive momentum distributions and by the Boltzmann--Gibbs statistics.~It is…

High Energy Physics - Phenomenology · Physics 2019-05-23 Keming Shen , Gergely Gábor Barnaföldi , Tamás Sándor Biró

A study of the effects of non-extensivity on the modelling of atomic physics in hot dense plasmas is proposed within Tsallis' statistics. The electronic structure of the plasma is calculated through an average-atom model based on the…

Plasma Physics · Physics 2015-05-30 Jean-Christophe Pain , Denis Teychenné , Franck Gilleron

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 study the effects of dark-matter annihilation during the epoch of big-bang nucleosynthesis on the primordial abundances of light elements. We improve the calculation of the light-element abundances by taking into account the effects of…

High Energy Physics - Phenomenology · Physics 2015-10-28 Masahiro Kawasaki , Kazunori Kohri , Takeo Moroi , Yoshitaro Takaesu

To elucidate the significance of the effect of systematic uncertainties in light element abundance estimates on cosmological bounds derivable from Big Bang Nucleosynthesis (BBN) we present tables giving bounds on $\Omega_{baryon}$ and…

Astrophysics · Physics 2009-10-22 Lawrence M. Krauss , Peter J. Kernan

We analyze the effect of a variation of the strange nucleon matrix element $\langle N| m_s \bar{s}s|N\rangle$ on the abundances of the light elements produced in the Big Bang. For that, we vary the nucleon mass in the leading eight…

High Energy Physics - Phenomenology · Physics 2025-02-24 Ulf-G. Meißner , Bernard Metsch , Helen Meyer

The current status of big bang nucleosynthesis is reviewed. Particular attention is given to the degree at which the theory is consistent with the observation of the light element abundances.

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

The properties of the nonextensive parameter q and the Tsallis distribution for self-gravitating systems are studied. A mathematical expression of q is deduced based on the generalized Boltzmann equation, the q-H theorem and the generalized…

Statistical Mechanics · Physics 2015-08-10 Jiulin Du

The successful prediction of light element abundances from Big Bang Nucleosynthesis has been a pillar of the standard model of Cosmology. Because many of the relevant reaction rates are sensitive to the values of fundamental constants, such…

High Energy Physics - Phenomenology · Physics 2009-11-11 Baojiu Li , Ming-Chung Chu

We extend previous studies of big bang nucleosynthesis, with the assumption that ordinary matter and dark matter sectors are entangled through the number of degrees of freedom entering the Friedmann equations. This conjecture allows us to…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-28 C. A. Bertulani , V. Challa , J. J. He , S. Q. Hou , Ravinder Kumar

The effects of radiatively decaying, long-lived particles on big-bang nucleosynthesis (BBN) are discussed. If high-energy photons are emitted after BBN, they may change the abundances of the light elements through photodissociation…

High Energy Physics - Phenomenology · Physics 2008-11-26 Erich Holtmann , M. Kawasaki , K. Kohri , Takeo Moroi