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Related papers: Big Bang Nucleosynthesis: 2015

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Assuming the lightest neutralino forms dark matter, we study its residual annihilation after freeze-out at the early universe. If taking place after the big bang nucleosynthesis (BBN) the annihilation products, especially at the hadronic…

High Energy Physics - Phenomenology · Physics 2008-04-17 Xiao-Jun Bi

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

Assuming the best numerical value for the cosmic baryonic density and the existence of three neutrino flavors, standard big bang nucleosynthesis is a parameter-free model. It is important to assess if the observed primordial abundances can…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-07 Christian Iliadis , Alain Coc

In big bang nucleosynthesis (BBN), the light matter abundance is dictated by the neutron-to-proton ($n/p$) ratio which is controlled by the standard weak processes in the early universe. Here, we study the effect of an extra particle…

High Energy Physics - Phenomenology · Physics 2024-06-24 Deep Ghosh

Within the standard big bang nucleosynthesis (BBN) and cosmic microwave background (CMB) framework, the baryon density measured by the Wilkinson Microwave Anisotropy Probe (WMAP) or the primordial D abundance is much higher than the one…

Astrophysics · Physics 2009-11-10 Kazuhide Ichikawa , Masahiro Kawasaki , Fuminobu Takahashi

A review of the latest measurements of the primordial abundances of the light nuclei D, 3He, 4He and 7Li is given. We discuss in particular the primordial abundance Yp of 4He as measured in blue compact dwarf galaxies. We argue that the…

Astrophysics · Physics 2007-05-23 T. X. Thuan , Y. I. Izotov

Standard big bang nucleosynthesis (BBNS) promises accurate predictions of the primordial abundances of deuterium, helium-3, helium-4 and lithium-7 as a function of a single parameter. Previous measurements have nearly always been…

Astrophysics · Physics 2008-02-03 Scott Burles , David Tytler

We present the Big-Bang Nucleosynthesis (BBN) simulation with a bubble universe scenario around a rotating black hole (BH) in Kerr-AdS$_5$ spacetime to explain recently updated observations of light elements such as the primordial helium…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-17 Akira Dohi , Issei Koga , Kazushige Ueda

This is a reply report to astro-ph/0604264. We studied heavy element production in high baryon density region in early universe astro-ph/0507439. However it is claimed in astro-ph/0604264 that small scale but high baryon density region…

Astrophysics · Physics 2009-11-13 Shunji Matsuura , Shin-ichirou Fujimoto , Masa-aki Hashimoto , Katsuhiko Sato

We present a simple method for determining the (correlated) uncertainties of the light element abundances expected from big bang nucleosynthesis, which avoids the need for lengthy Monte Carlo simulations. Our approach helps to clarify the…

Astrophysics · Physics 2009-10-07 G. Fiorentini , E. Lisi , Subir Sarkar , F. L. Villante

The cosmic energy density in the form of radiation before and during Big Bang Nucleosynthesis (BBN) is typically parameterized in terms of the effective number of neutrinos N_eff. This quantity, in case of no extra degrees of freedom,…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 G. Mangano , G. Miele , S. Pastor , O. Pisanti , S. Sarikas

A brief review of standard big bang nucleosynthesis theory and the related observations of the light element isotopes is presented. Implications of BBN on chemical evolution and constraints on particle properties will also be discussed.

Astrophysics · Physics 2009-09-15 Keith A. Olive

Effects of light millicharged dark matter particles on primordial nucleosynthesis are considered. It is shown that if the mass of such particles is much smaller than the electron mass, they lead to strong overproduction of Helium-4. An…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Zurab Berezhiani , Aleksander Dolgov , Igor Tkachev

We revisit the big bang nucleosynthesis (BBN) limits on primordial magnetic fields and/or turbulent motions accounting for the decaying nature of turbulent sources between the time of generation and BBN. This leads to larger estimates for…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-22 Tina Kahniashvili , Emma Clarke , Jonathan Stepp , Axel Brandenburg

Big Bang Nucleosynthesis (BBN) and the Cosmic Background Radiation (CBR) provide complementary probes of the early evolution of the Universe and of its particle content. Neutrinos play important roles in both cases, influencing the…

Astrophysics · Physics 2007-05-23 Gary Steigman

Data from future high-precision Cosmic Microwave Background (CMB) measurements will be sensitive to the primordial Helium abundance $Y_p$. At the same time, this parameter can be predicted from Big Bang Nucleosynthesis (BBN) as a function…

Astrophysics · Physics 2009-03-24 Jan Hamann , Julien Lesgourgues , Gianpiero Mangano

A massive long-lived tau neutrino in the MeV regime modifies the primordial light-element abundances predicted by big-bang nucleosynthesis (BBN) calculations. This effect has been used to derive limits on the tau neutrino mass. Because…

Astrophysics · Physics 2011-05-23 J. B. Rehm , G. G. Raffelt , A. Weiss

We derive constraints on the injection of free-streaming dark radiation after big bang nucleosynthesis (BBN) by considering the decay of a massive hidden sector particle into dark radiation. Such a scenario has the potential to alleviate…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-12 Alexander C. Sobotka , Adrienne L. Erickcek , Tristan L. Smith

A brief overview of non-standard big bang nucleosynthesis (BBN) scenarios is presented. Trends and results of the light-element nucleosynthesis in BBN scenarios with small-scale or large-scale inhomogeneity, the presence of antimatter…

Astrophysics · Physics 2007-05-23 Karsten Jedamzik

Thanks to the accurate determination of the baryon density of the universe by the recent cosmic microwave background experiments, updated predictions of the standard model of Big Bang nucleosynthesis now yield the initial abundance of the…

Astrophysics · Physics 2015-06-24 C. Charbonnel , F. Primas