<i>Suzaku</i> Observations Of The North Polar Spur: A Window To C And N Emission
Abstract
The North Polar Spur (NPS) is a region of enhanced soft X-ray and radio emission extending above the plane of the Galaxy. The source of this emission is uncertain, with theories ranging from a nearby supernova remnant to a hot bubble produced by a nearby OB association to a bipolar shell from a recent nuclear starburst episode. The relative chemical abundances and the plasma conditions within the NPS hold the key to its formation.We present observations of the North Polar Spur using the X-ray Imaging Spectrometer (XIS) aboard the <i>Suzaku</i> X-ray satellite, a joint Japanese-US mission launched in July 2005. The exceptional sensitivity and spectral resolution of the XIS below 1 keV allow unprecedented probing of low-energy spectral lines, and we have detected the CVI and NVII emission lines toward the North Polar Spur for the first time. The best-fit emission model implies a hot (kT 0.25-0.3 keV), CIE plasma with depleted abundances of less than 0.5 solar, but an enhanced N abundance with N/O 3-5 solar. We discuss these results in the context of the possible formation scenarios of this component and the hot diffuse Galactic emission in general.
- Publication:
-
American Astronomical Society Meeting Abstracts #208
- Pub Date:
- June 2006
- Bibcode:
- 2006AAS...208.3504M