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搜索结果: 1-15 共查到理学 Nucleosynthesis相关记录19条 . 查询时间(0.14 秒)
Although the rapid neutron-capture process, or r-process, is fundamentally important for explaining the origin of approximately half of the stable nuclei with A > 60, the astrophysical site of this pr...
Products from massive-star nucleosynthesis have been measured with SPI on INTEGRAL: Characteristic gamma-ray lines from radioactive decays of long-lived 26Al and 60Fe isotopes, and from 44Ti decay (de...
The theoretical predictions of the primordial abundances of elements in the big-bang nucleosynthesis (BBN) are dominated by uncertainties in the input nuclear reaction rates. We investigate the effect...
Many hydrogen deficient stars are characterised by surface abundance patterns that are hard to reconcile with conventional stellar evolution. Instead, it has been suggested that they may represent the...
The origin of the iron-group elements titanium to zinc in nature is understood to occur under explosive burning conditions in both Type Ia (thermonuclear) and Type II (core collapse) supernovae. In th...
Primordial or Big Bang nucleosynthesis (BBN) is one of the three strong evidences for the Big- Bang model together with the expansion of the Universe and the Cosmic Microwave Background radiation. In ...
We discuss theoretical AGB predictions for hydrogen-deficient PG 1159 stars and Sakurai's object, which show peculiar enhancements in He, C and O, and how these enhancements may be understood in the f...
We discuss the characteristics of known extremely metal-poor (EMP) stars in the Galaxy using the Stellar Abundances for Galactic Archaeology (SAGA) database (Suda et al. 2008, PASJ, 60, 1159).The anal...
We show how recent data from observations of the cosmic microwave background may suggest the presence of additional radiation density which appeared after big bang nucleosynthesis. We propose a gener...
The recently claimed observations of non-negligible amounts of 6Li in old halo stars have renewed interest in the Big-Bang Nucleosynthesis (BBN) of 6Li. One important ingredient in the predicted BBN a...
We show how recent data from observations of the cosmic microwave back-ground may suggest the presence of additional radiation density which appeared after big bang nucleosynthesis. We propose a gener...
We study the evolution of primordial neutrino{antineutrino asymmetries in the early universe, before and during Big Bang Nucleosynthesis (BBN). We consider quite a wide range for the total lepton numb...
During the evolution on the AGB, S-type stars are the first objects to experience s-process nucleosynthesis and third dredge-ups, and therefore to exhibit sprocess signatures in their atmospheres.
We present high resolution observations of an extremely metal-poor damped Ly system, at zabs = 2.3400972 in the spectrum of the QSO J0035−0918, exhibiting an abundance pattern consistent with mo...
Big bang nucleosynthesis (BBN), an epoch of primordial nuclear transforma-tions in the expanding Universe, has left an observable imprint in the abundances of light elements. Precision observations of...

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