A Spectroscopic Study of Nuclear Processing and the Production of Anomalously Strong Lines in the Crab Nebula

  title={A Spectroscopic Study of Nuclear Processing and the Production of Anomalously Strong Lines in the Crab Nebula},
  author={G. M. Macalpine and T. C. Ecklund and W. Ryan Lester and Steven J. Vanderveer and Lehigh University and Western Kentucky University},
  journal={The Astronomical Journal},
We present and discuss correlations for optical and near-infrared (5500-10030 A) line intensity measurements at many positions in the Crab Nebula. These correlations suggest the existence of gas produced by a range of nuclear processing, from material in which synthesis ended with the CNO cycle, to some helium burning and nitrogen depletion, to regions containing enriched products of oxygen burning. The latter exhibit a gradual, linear rise of [Ni II] emission with increasing argon enrichment… Expand
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