ar X iv : a st ro - p h / 01 01 43 8 v 1 2 4 Ja n 20 01 NUCLEAR
نویسنده
چکیده
Observations of metal-poor Galactic halo stars indicate that the abundance pattern of the (heaviest) neutron-capture elements is consistent with the scaled solar system r-process abundances. Utilizing the radioactive (r-process) element thorium, age determinations have been made for several of these same stars, placing constraints on both Galactic and cosmological age estimates.
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ar X iv : a st ro - p h / 97 01 22 8 v 1 2 9 Ja n 19 97 Large - scale Structures revealed by Wavelet Decomposition 1
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تاریخ انتشار 2001