Measurement of stellar age from uranium decay

  title={Measurement of stellar age from uranium decay},
  author={Roger. Cayrel and Vanessa Hill and Timothy C. Beers and Beatriz Barbuy and Monique Spite and Franccois Spite and Bertrand Plez and J. Andersen and Piercarlo Bonifacio and P. François and Paolo Molaro and B. Nordstr{\"o}m and Francesca Primas},
The ages of the oldest stars in the Galaxy indicate when star formation began, and provide a minimum age for the Universe. Radioactive dating of meteoritic material and stars relies on comparing the present abundance ratios of radioactive and stable nuclear species to the theoretically predicted ratios of their production. The radioisotope 232Th (half-life 14 Gyr) has been used to date Galactic stars, but it decays by only a factor of two over the lifetime of the Universe. 238U (half-life 4.5… 

Radioactive Ages of Metal-Poor Halo Stars

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The U/Th abundance ratio in meteorites can be used, in conjunction with observations of low-metallicity stars in the halo of the Milky Way, to determine the U/ Th production ratio very precisely, which can be use in future studies to constrain the possible nuclear mass formulae used in r-process calculations.

The age of the Galactic thin disk from Th/Eu nucleocosmochronology - II. Chronological analysis

The purpose of this work is to resume investigation of Galactic thin disk dating using nucleocosmochronology with Th/Eu stellar abundance ratios, a theme absent from the literature since 1990.

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A stellar relic from the early Milky

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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



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Observation of the radioactive nuclide 232Th (half life 14 Gyr) in stars of various ages offers the possibility of directly relating the timescale for nucleosynthesis to that for stellar and galactic

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Recent observations of r-nuclei, and in particular of Th, in ultra-metal poor stars revived the old idea that the Th cosmochronometry could provide an age estimate of the oldest stars in the Galaxy,

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The concordance of scaled solar r-process and CS 22892-052 abundances breaks down for the lighter neutron-capture elements, supporting previous suggestions that different r- process production sites are responsible for lighter and heavier neutron- capture elements.

r-Process Abundances and Chronometers in Metal-poor Stars

Rapid neutron-capture (i.e., r-process) nucleosynthesis calculations, employing internally consistent and physically realistic nuclear physics input (quasi-particle random-phase approximation [QRPA]

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New high resolution, very high signal-to-noise spectra of ultra-metal-poor (UMP) giant stars HD 115444 and HD 122563 have been gathered with the High-Resolution Echelle Spectrometer of the McDonald

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In this paper, we present new measurements of the thorium and europium abundances in metal poor stars. We found the [Th/Fe] and [Eu/Fe] ratios to be oversolar in halo stars down to the metallicity

Meteorites and the early solar system

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