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Suzaku Reveals Helium-burning Products in the X-ray Emitting Planetary Nebula BD+303639

M. Murashima·M. Kokubun·K. Makishima·J. Kotoku·H. Murakami·K. Matsushita·K. Hayashida·K. Arnaud·K. Hamaguchi·H. Matsumoto
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Abstract

BD+303639, the brightest planetary nebula at X-ray energies, was observed with Suzaku, an X-ray observatory launched on 2005 July 10. Using the X-ray Imaging Spectrometer, the K-lines from C VI, O VII, and O VIII were resolved for the first time, and C/O, N/O, and Ne/O abundance ratios determined. The C/O and Ne/O abundance ratios exceed the solar value by a factor of at least 30 and 5, respectively. These results indicate that the X-rays are emitted mainly by helium shell-burning products.

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M. Murashima, M. Kokubun, K. Makishima, J. Kotoku, H. Murakami, K. Matsushita, K. Hayashida, K. Arnaud, K. Hamaguchi, H. Matsumoto. 2006-07-07. Suzaku Reveals Helium-burning Products in the X-ray Emitting Planetary Nebula BD+303639. https://doi.org/10.1086/507465

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