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The soft X-ray background towards the northern sky. A detailed analysis of the Milky Way halo

J. Pradas·J. Kerp·P. M. W. Kalberla
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Abstract

We present a correlation analysis of the diffuse X-ray background emission of the ROSAT all-sky survey with the Leiden/Dwingeloo 21-cm HI line survey. We derive a consistent model for the diffuse X-ray background emission over about 50% of the sky. Only three diffuse X-ray components are necessary to fit the ROSAT data from 0.1 keV to 2.4 keV: a) the Local Hot Bubble, b) the Milky Way Halo, and c) the extragalactic X-ray background. Only one temperature of the hot coronal gas in the Milky Way Halo is needed. Our model predicts, that a major fraction of the 1/4 keV and about 50% of the 3/4 keV diffuse X-ray emission originates from the Milky Way Halo. We detect a difference between the intensities towards the Galactic center and its anti-center, which is consistent with the electron density distribution independently derived from pulsar dispersion measurements.

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J. Pradas, J. Kerp, P. M. W. Kalberla. 2002-11-19. The soft X-ray background towards the northern sky. A detailed analysis of the Milky Way halo. https://doi.org/10.1002/asna.200310049

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