High-resolution X-ray spectroscopy of the planetary nebula BD+303639
Abstract
We present the results of the first X-ray gratings spectroscopy observations of a planetary nebula (PN) - the X-ray-bright, young BD +30 3639. We observed BD +30 3639 for a total of ~300 ks with the Chandra X- ray Observatory's Low Energy Transmission Gratings in combination with its Advanced CCD Imaging Spectrometer (LETG/ACIS-S). The LETG/ACIS results indicate that the X-ray source originates essentially from the present-day stellar wind (Ne/O and C/O are greatly enhanced over solar, while Fe/O is subsolar) and suggest the presence of a range of plasma temperatures from Tx ~ 1.7 MK to 2.9 MK and an intervening absorbing column NH ~ 2.4 x 10^21 cm^-2. The range of temperatures implied by the plasma model fitting offers the first direct indication of the presence of a temperature gradient within the wind-collision-generated 'hot bubble' of a planetary nebula, providing much-needed constraints on wind collision models; while the results for plasma abundances are important in the context of theories of nucleosynthesis during advanced evolutionary stages of intermediate-mass stars.
- Publication:
-
High Resolution X-ray Spectroscopy: Towards IXO
- Pub Date:
- September 2009
- Bibcode:
- 2009hrxs.confE..49Y