Isotopic Composition and Abundance of Interstellar Neutral Helium Based on Direct Measurements

  title={Isotopic Composition and Abundance of Interstellar Neutral Helium Based on Direct Measurements},
  author={Georgy N. Zastenker and Emma Salerno and Fr{\'e}d{\'e}ric U. Buehler and Peter A. Bochsler and M. L. Bassi and Yu. N. Agafonov and N. A. Eismont and Vladimir V. Khrapchenkov and Henner Busemann},
One of the important problems in astrophysics is the determination of the abundances of the helium isotopes 3He and 4He in various regions of the universe, since those abundances can provide evidence of the intensities of various possible processes of the production and decay of light elements and can thereby reflect their history. In this paper we describe the procedure and results of the first determination by a direct method of the abundances of helium isotopes in the local interstellar… Expand
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