The Radiation Transfer of Soft X-rays
Abstract
We discuss the link between the halo plasma temperature and the power-law spectral index of the extragalactic background radiation. This link is of strong influence for the derivation of the Galactic halo intensity distribution. In principal, we can distinguish between two combinations of Galactic halo plasma temperature and power-law slope. The first combination consists of a halo plasma of T_halo = 10^6 K and an E^{-2} approximation of the extragalactic background radiation. The second combination is T_halo = 10^{6.2} K and E^{-1.5}. Both combinations are in agreement with recent observational results, thus it is not feasible to discriminate between both models on the basis of X-ray data available. But, the soft X-ray background intensity distribution in the 1/4 keV and 3/4 keV ROSAT energy bands differs significantly. The T_halo = 106 K, E^{-2} allows a patchy 1/4 keV intensity distribution while the T_halo = 10^{6.2} K, E^{-1.5} predicts a much smoother intensity variation since the hotter halo plasma accounts for a significant fraction of the 3/4 keV background radiation.
- Publication:
-
IAU Colloq. 166: The Local Bubble and Beyond
- Pub Date:
- 1998
- DOI:
- 10.1007/BFb0104744
- Bibcode:
- 1998LNP...506..337K