Results 1 to 10 of about 21,814 (256)
Magellanic Clouds Cepheids: Thorium Abundances [PDF]
Journal of Astronomy and Space Sciences, 2018 The analysis of the high-resolution spectra of 31 Magellanic Clouds Cepheid variables enabled the identification of thorium lines. The abundances of thorium were found with spectrum synthesis method. The calculated thorium abundances exhibit correlations
Yeuncheol Jeong +5 more
doaj +1 more source
Núcleos exóticos e síntese dos elementos químicos
Química Nova, 2012 We have around ninety chemical elements available in nature, which were produced mainly by nuclear reactions inside stars. The fusion reactions are the main synthesis process which generates the light and intermediate masses elements.
Nilton Teruya, Sérgio Barbosa Duarte
doaj +1 more source
Screening Effects in Stars and in the Laboratory
Frontiers in Physics, 2022 Nuclear reactions are the driver of the evolution of many astrophysical objects. In the astrophysical environment their respective reaction rates are, however, modified due to the presence of other charges.
Marialuisa Aliotta +2 more
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R-Process with Magnetized Nuclei at Dynamo-Explosive Supernovae and Neutron Star Mergers
Universe, 2021 Nucleosynthesis at latge magnetic induction levels relevant to core-collapse supernovae and neutron star mergers is considered. For respective magnetic fields of a strength up to ten teratesla, atomic nuclei exhibit a linear magnetic response due to the ...
Vladimir N. Kondratyev
doaj +1 more source
Hydrogen Tunneling in Stoichiometric and Catalytic Reactions involving Transition Metals
ChemCatChem, Volume 15, Issue 24, December 19, 2023., 2023 An overview on the importance of the participation of hydrogen tunneling in E−H bond activation reactions (E=C, O, Si…) mediated by transition metals is presented. Understanding when hydrogen tunneling occurs can be a powerful tool for designing new catalysts to perform challenging reactions.
Jon M. Matxain, Miguel A. Huertos
wiley +1 more source
Primordial nucleosynthesis [PDF]
Proceedings of the National Academy of Sciences, 1998 With the advent of the new extragalactic deuterium observations, Big Bang nucleosynthesis (BBN) is on the verge of undergoing a transformation. In the past, the emphasis has been on demonstrating the concordance of the BBN model with the abundances of the light isotopes extrapolated back to their primordial values by using stellar and
openaire +2 more sources
Big bang nucleosynthesis constraints on sterile neutrino and lepton asymmetry of the Universe [PDF]
Journal of Cosmology and Astroparticle Physics, 2020 We consider the cosmological effects of sterile neutrinos with the masses of 150–450 MeV . The decay of sterile neutrinos changes the thermal history of the Universe and affects the energy density of radiation at recombination and the big bang ...
G. Gelmini +4 more
semanticscholar +1 more source
Indirect Measurements of n- and p-Induced Reactions of Astrophysical Interest on Oxygen Isotopes
Frontiers in Astronomy and Space Sciences, 2020 Observations of abundances and isotopic ratio determinations in stars yield powerful constraints on stellar models. In particular, the oxygen isotopic ratios are of particular interest because they are affected not only by nucleosynthesis but also by ...
M. L. Sergi +12 more
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s-Processing in Asymptotic Giant Branch Stars in the Light of Revised Neutron-Capture Cross Sections
Universe, 2021 Current AGB stellar models provide an adequate description of the s-process nucleosynthesis that occurs. Nonetheless, they still suffer from many uncertainties related to the modeling of the 13C pocket formation and the adopted nuclear reaction rates ...
Diego Vescovi, René Reifarth
doaj +1 more source
Annalen der Physik, Volume 535, Issue 12, December 2023., 2023 This article describes the implementation of low‐frequency axion haloscope setups inside the future BabyIAXO magnet. The RADES proposal has a potential sensitivity to the axion‐photon coupling down to values corresponding to the KSVZ model, in the mass range between 1 and 2 μ$\umu$eV.
Saiyd Ahyoune +29 more
wiley +1 more source