Results 81 to 90 of about 22,632 (204)
Incomplete neutrino decoupling effect on big bang nucleosynthesis [PDF]
Physical Review D, 2019 In the primordial Universe, neutrino decoupling occurs only slightly before electron-positron annihilations, leading to an increased neutrino energy density with order $10^{-2}$ spectral distortions compared to the standard instantaneous decoupling ...
Julien Froustey, C. Pitrou
semanticscholar +1 more source
Big Bang Nucleosynthesis constraints on f(T,T) gravity
Physics Letters BBig 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 Relativity, it is ...
Sai Swagat Mishra +2 more
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Big Bang nucleosynthesis constraint on baryonic isocurvature perturbations [PDF]
Journal of Cosmology and Astroparticle Physics, 2018 We study the effect of large baryonic isocurvature perturbations on the abundance of deuterium (D) produced in big bang nucleosynthesis (BBN). Large baryonic isocurvature perturbations existing at the BBN epoch (T∼ 0.1 MeV) change the D abundance by a ...
Keisuke Inomata +3 more
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Big-bang nucleosynthesis and cosmic microwave background constraints on nonminimally coupled theories of gravity [PDF]
Physical Review D, 2018 In this paper we show that the baryon-to-photon ratio $\eta$ is in general not conserved before decoupling in non-minimally coupled theories of gravity. We use big-bang nucleosynthesis and cosmic microwave background limits on the baryon-to-photon ratio $
R. Azevedo, P. Avelino
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3He(α,γ)7Be cross section measured using complementary techniques
EPJ Web of Conferences, 2014 The astrophysical S-factor for the 3He(α,γ)7Be reaction plays an important role in the Solar Standard Model and in the Big Bang Nucleosynthesis scenario. The advances from two recent experiments performed using complementary techniques at center of mass (
Carmona-Gallardo M. +8 more
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Spacetime deformation effect on the early universe and the PTOLEMY experiment
Physics Letters B, 2017 Using a fully-fledged formulation of gauge field theory deformed by the spacetime noncommutativity, we study its impact on relic neutrino direct detection, as proposed recently by the PTOLEMY experiment.
Raul Horvat +2 more
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Revisiting big-bang nucleosynthesis constraints on dark-matter annihilation
Physics Letters B, 2015 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 anti-nucleons ...
Masahiro Kawasaki +3 more
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Universe, 2020 One of the most important issues in an inflationary theory as standard or quintessential inflation is the mechanism to reheat the universe after the end of the inflationary period in order to match with the Hot Big Bang universe.
Jaume Haro Cases, Llibert Aresté Saló
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EPJ Web of Conferences, 2018 We briefly describe the cosmological lithium problems followed by a summary of our recent theoretical work on the magnitude of the effects of electron screening, thepossible existence of dark matter parallel universes and the use of non-extensive (Tsal ...
Bertulani C.A. +2 more
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θ-dependence of light nuclei and nucleosynthesis
Physical Review Research, 2020 We investigate the impact of the QCD vacuum at nonzero θ on the properties of light nuclei, Big Bang nucleosynthesis, and stellar nucleosynthesis. Our analysis starts with a calculation of the θ-dependence of the neutron-proton mass difference and ...
Dean Lee +4 more
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