The Nature of the Spatial Structure of Diffuse Soft X-Rays in the Direction of the North Polar Spur.

The spatial structure of the X-ray sky in the direction of the North Polar Spur was examined in two energy bands, the B band (0.1 - 0.18 keV) and, the C band (0.1 - 0.28 keV). The data are shown to be inconsistent with thermal emission, absorbed or unabsorbed, from a single region at any single temperature. They are also inconsistant with the sum of emission from two separate regions, each at a different temperature, with a constant amount of absorption. A model with two emitting regions, one local with unabsorbed emission, and the other more distant with emission partially absorbed by spatially varying amounts of material was investigated. This model was compared to the data from several sounding rocket flights to derive the spatial distribution of absorbing material necessary for the model to reproduce the observed soft X-ray spatial variations.