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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
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Structure formation cosmic rays: Identifying observational constraints [PDF]
Serbian Astronomical Journal, 2005 Shocks that arise from baryonic in-fall and merger events during the structure formation are believed to be a source of cosmic rays. These "structure formation cosmic rays" (SFCRs) would essentially be primordial in composition, namely, mostly made of ...
Prodanović T., Fields B.D.
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Inhomogeneous Big-Bang Nucleosynthesis in Light of Recent Observations [PDF]
, 1998 We consider inhomogeneous big bang nucleosynthesis in light of the present observational situation. Different observations of He-4 and D disagree with each other, and depending on which set of observations one uses, the estimated primordial He-4 ...
Kainulainen, K. +2 more
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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
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
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Reheating Temperature and Gauge Mediation Models of Supersymmetry Breaking [PDF]
, 2009 For supersymmetric theories with gravitino dark matter, the maximal reheating temperature consistent with big bang nucleosynthesis bounds arises when the physical gaugino masses are degenerate.
A. Rizzi . +28 more
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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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Cosmological and astrophysical bounds on a heavy sterile neutrino and the KARMEN anomaly [PDF]
, 2000 Constraints on the lifetime of the heavy sterile neutrino, that was proposed as a possible interpretation of the KARMEN anomaly, are derived from primordial nucleosynthesis and SN 1987A.
A.D. Dolgov +30 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
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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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