The cosmological density of baryons from observations of 3He+ in the Milky Way

@article{Bania2002TheCD,
  title={The cosmological density of baryons from observations of 3He+ in the Milky Way},
  author={T. M. Bania and Robert T. Rood and Dana. S. Balser},
  journal={Nature},
  year={2002},
  volume={415},
  pages={54-57}
}
Primordial nucleosynthesis after the Big Bang can be constrained by the abundances of the light elements and isotopes 2H, 3He, 4He and 7Li (ref. 1). The standard theory of stellar evolution predicts that 3He is also produced by solar-type stars, so its abundance is of interest not only for cosmology, but also for understanding stellar evolution and the chemical evolution of the Galaxy. The 3He abundance in star-forming (H II) regions agrees with the present value for the local interstellar… 

Galactic evolution of D, 3He and 4He

  • D. Romano
  • Physics
    Proceedings of the International Astronomical Union
  • 2009
Abstract The uncertainties which still plague our understanding of the evolution of the light nuclides D, 3He and 4He in the Galaxy are described. Measurements of the local abundance of deuterium

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Standard stellar evolution models that only consider convection as a physical process to mix material inside of stars predict the production of significant amounts of 3He in low-mass stars (M < 2 M

Big bang nucleosynthesis

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