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Rhenium-187 and the age of the galaxy
The sixteenth international conference on atomic physics, 1999The amount of 187Os in meteorites resulting from beta decay of the long-lived 187Re nuclide has been used as a measure of the time span of nucleosynthesis in our galaxy. During the galactic history, however, the rhenium atoms can be “astrated” several times into newly forming stars, where they are stripped of most or all of their electrons.
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Sulphur in the Early Ages of the Galaxy
2006International audience ; We present here the results of the measurement of the sulphur abundance in very metal-poor stars. Our sample covers the [-4;-2] range of metallicity, and thus allows us to constraint the chemical evolution models and also to put some key constraints on the supernovae models.
Depagne, Éric +12 more
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The Age of the First Nucleosynthesis in the Galaxy
2004The observation of extremely metal-poor stars makes possible to obtain the epoch of formation of the first elements produced by massive supernovae, or hypernovae. The classical way of obtaining stellar ages (isochrone fitting) is unfortunately not applicable at present, as the distances of these stars are not known with enough accuracy. Dating by decay
Cayrel, R. +13 more
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Constraining Cosmological Parameters Based on Relative Galaxy Ages
Astrophysical Journal, 2002Raúl Jiménez, Abraham Loeb
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