Observation of interstellar lithium in the low-metallicity Small Magellanic Cloud

  title={Observation of interstellar lithium in the low-metallicity Small Magellanic Cloud},
  author={J. Christopher Howk and Nicolas Lehner and Brian D. Fields and Grant J. Mathews},
The primordial abundances of light elements produced in the standard theory of Big Bang nucleosynthesis (BBN) depend only on the cosmic ratio of baryons to photons, a quantity inferred from observations of the microwave background. The predicted primordial 7Li abundance is four times that measured in the atmospheres of Galactic halo stars. This discrepancy could be caused by modification of surface lithium abundances during the stars’ lifetimes or by physics beyond the Standard Model that… 
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The detection of interstellar lithium beyond the Milky Way, in the low-metallicity gas of the nearby Small Magellanic Cloud galaxy, shows that present-day lithium-7 abundance in this galaxy is nearly equal to the predictions of the standard theory of Big Bang nucleosynthesis — although the data can also be reconciled with non-standard models.
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