Results 1 to 10 of about 307 (107)
Nuclear cosmochronology with customized initial abundances of radioactive nuclides [PDF]
EPJ Web of ConferencesThe recent developments in the studies of nuclear cosmochronology are reviewed. Nuclear cosmochronology, which predicts the ages of the stars by comparing the present and initial abundances of longlived radioactive nuclides, provides an independent ...
Wu Xin-Hui
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White dwarf cooling sequences and cosmochronology [PDF]
EPJ Web of Conferences, 2013 The evolution of white dwarfs is a simple gravothermal process. This means that their luminosity function, i.e. the number of white dwarfs per unit bolometric magnitude and unit volume as a function of bolometric magnitude, is a monotonically increasing ...
García-Berro E., Artigas A., Isern J.
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INHOMOGENEITIES OF CHEMICAL COMPOSITION AND COSMOCHRONOLOGY PROBLEMS
Odessa Astronomical Publications, 2017 The problems of determination of chemical composition of stars and connection with theory of chemical evolution of Galaxy are discussed.
V. G. Klochkova, V. E. Panchuk
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Correlation Between U/Th and Pb/Os Abundance Ratios and Its Application in Nuclear Cosmochronology
Astrophysical JournalThe abundance ratios of radioactive elements U/Th and stable elements Pb/Os from the r -process are found to have a strong correlation. This correlation is quite robust with respect to astrophysical conditions.
S Q Zhang, Y Y Huang
exaly +2 more sources
Nuclear reactions in astrophysics
Eurasian Journal of Physics and Functional Materials, 2021 This work is an attempt to present some problems on the evolution of the Universe: the nucleosynthesis and cosmochronology from the standpoint of physics of particles and nuclei, in particular with the use of the lat est results, obtained by means of ...
Yu. E. Penionzhkevich
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The Astrophysical Journal Letters, 2023 We present a U-corrected Pb–Pb age of 4566.19 ± 0.20 Ma (1.11 ± 0.26 Myr after t _0 ) for the moderately volatile element rich, andesitic meteorite Erg Chech 002 (EC002). Our Al–Mg isochron defines a ^26 Al/ ^27 Al initial ratio of (8.65 ± 0.09) × 10 ^−6
J. N. Connelly +5 more
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The Planetary Science Journal, 2023 The history of accretion and differentiation processes in the planetesimals is provided by various groups of meteorites. Sampling different parent body layers, they reveal the circumstances of the metal–silicate segregation and the internal structures of
Wladimir Neumann +4 more
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The Q Branch Cooling Anomaly Can Be Explained by Mergers of White Dwarfs and Subgiant Stars
The Astrophysical Journal Letters, 2023 Gaia's exquisite parallax measurements allowed for the discovery and characterization of the Q branch in the Hertzsprung–Russell diagram, where massive C/O white dwarfs (WDs) pause their dimming due to energy released during crystallization ...
Ken J. Shen +2 more
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Uranium Abundances and Ages of r-process Enhanced Stars with Novel U ii Lines
The Astrophysical Journal, 2023 The ages of the oldest stars shed light on the birth, chemical enrichment, and chemical evolution of the universe. Nucleocosmochronometry provides an avenue to determining the ages of these stars independent from stellar-evolution models.
Shivani P. Shah +9 more
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R‐Process Nucleosynthesis in MHD Jet Explosions of Core‐Collapse Supernovae
Journal of Astrophysics, Volume 2013, Issue 1, 2013., 2013 We investigate the r‐process nucleosynthesis during the magnetohydrodynamical (MHD) explosion of a supernova in a helium star of 3.3 M⊙, where effects of neutrinos are taken into account using the leakage scheme in the two‐dimensional (2D) hydrodynamic code.
Motoaki Saruwatari +6 more
wiley +1 more source