Suzaku Reveals Helium-burning Products in the X-Ray-emitting Planetary Nebula BD +30 3639
Hamaguchi, K.; Matsushita, K.; Hayashida, K.; Murakami, H.; Makishima, K.; Kokubun, M.; Matsumoto, H.; Murashima, M.; Kotoku, J.; Arnaud, K.
Japan, United States
Abstract
BD +30 3639, 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 the C/O, N/O, and Ne/O abundance ratios were determined. The C/O and Ne/O abundance ratios exceed the solar value by factors of at least 30 and 5, respectively. These results indicate that the X-rays are emitted mainly by helium-shell-burning products.