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- Q922682 subject Q6398965.
- Q922682 subject Q6441178.
- Q922682 abstract "The Spite plateau (or Spite lithium plateau) is a baseline in the abundance of lithium found in old stars orbiting the galactic halo. It was named after the astronomers François and Monique Spite, who published the discovery in 1982.The element lithium was first produced during the Big Bang that created the observable universe. The cosmic abundance of lithium is of interest because it provides several constraints to the various Big Bang models. Those models that fail to satisfy these constraints are therefore subject to rejection or correction by the scientific community.Lithium is readily consumed by fusion with protons at temperatures above 2 × 106 K, such as is found in the cores of stars. Thus, if the convection zone of a main sequence star carries lithium to the core region, the abundance of lithium in the star can decrease. Likewise, lithium can be produced in interstellar matter by spallation collisions with cosmic rays, or by the evolution of stars of moderate mass.To obtain a good estimate of the primordial abundance of lithium, astronomers François and Monique Spite measured the abundance of lithium in old, population II stars (or old halo stars). Such stars were formed early in the universe out of material that had not been significantly modified by other processes. Their results showed that the curve on a graph of the abundance of lithium versus effective surface temperature formed a plateau among old halo stars for effective temperatures below about: log Teff ~ 3.75or roughly 5,600 K. This suggested that the plateau represented the primordial abundance level of lithium in the Milky Way, and thus they were able to estimate that the abundance of lithium at the beginning of the galaxy was: NLi = (11.2 ± 3.8) × 10−11 NHwhere NH is the abundance of hydrogen.The current estimates for the primordial abundance of lithium, as measured by this technique, are in tension with the predictions of the standard model of Big Bang nucleosynthesis, a discrepancy known as the Lithium Problem.".
- Q922682 wikiPageWikiLink Q11547.
- Q922682 wikiPageWikiLink Q11579.
- Q922682 wikiPageWikiLink Q128034.
- Q922682 wikiPageWikiLink Q1436016.
- Q922682 wikiPageWikiLink Q221392.
- Q922682 wikiPageWikiLink Q321.
- Q922682 wikiPageWikiLink Q323.
- Q922682 wikiPageWikiLink Q3450.
- Q922682 wikiPageWikiLink Q41872.
- Q922682 wikiPageWikiLink Q568.
- Q922682 wikiPageWikiLink Q6398965.
- Q922682 wikiPageWikiLink Q6441178.
- Q922682 wikiPageWikiLink Q837317.
- Q922682 comment "The Spite plateau (or Spite lithium plateau) is a baseline in the abundance of lithium found in old stars orbiting the galactic halo. It was named after the astronomers François and Monique Spite, who published the discovery in 1982.The element lithium was first produced during the Big Bang that created the observable universe. The cosmic abundance of lithium is of interest because it provides several constraints to the various Big Bang models.".
- Q922682 label "Spite plateau".