| Autor: |
T H Heng, X D Xu, Z M Niu, B H Sun, J Y Guo |
| Předmět: |
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| Zdroj: |
Journal of Physics G: Nuclear & Particle Physics; Oct2014, Vol. 41 Issue 10, p1-1, 1p |
| Abstrakt: |
The cosmic age is an important physical quantity in cosmology. Based on the radiometric method, a reliable lower limit of the cosmic age is derived to be Gyr, using the r-process abundances inferred for the solar system and observations in metal-poor stars. If the central value is taken, this value is larger than the latest cosmic age Gyr determined from Planck 2013 results; however, the two agree with each other within uncertainties. The uncertainty of 1.94 Gyr mainly originates from the error on thorium abundance observed in metal-poor star CS 22892-052, so future high-precision abundance observations on CS 22892-052 are valuable to further check the cosmic age determined from different independent methods. On the other hand, by taking the cosmic age from Planck 2013 results as a standard value, the lower limit of abundance ratios Th/X and U/X in metal-poor stars is deduced as a guidance to future observations. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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