Cosmic X-ray background and Earth albedo Spectra with Swift/BAT

M. Ajello; J. Greiner; G. Sato; D. R. Willis; G. Kanbach; A. W. Strong; R. Diehl; G. Hasinger; N. Gehrels; C. B. Markwardt; J. Tueller

doi:10.1086/592595

arXiv · 0808.3377

Cosmic X-ray background and Earth albedo Spectra with Swift/BAT

M. Ajello·J. Greiner·G. Sato·D. R. Willis·G. Kanbach·A. W. Strong·R. Diehl·G. Hasinger·N. Gehrels·C. B. Markwardt·J. Tueller

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Abstract

We use Swift/BAT Earth occultation data at different geomagnetic latitudes to derive a sensitive measurement of the Cosmic X-ray background (CXB) and of the Earth albedo emission in the 15--200 keV band. We compare our CXB spectrum with recent (INTEGRAL, BeppoSAX) and past results (HEAO-1) and find good agreement. Using an independent measurement of the CXB spectrum we are able to confirm our results. This study shows that the BAT CXB spectrum has a normalization ~8(+/-3)% larger than the HEAO-1 measurement. The BAT accurate Earth albedo spectrum can be used to predict the level of photon background for satellites in low Earth and mid inclination orbits.

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M. Ajello, J. Greiner, G. Sato, D. R. Willis, G. Kanbach, A. W. Strong, R. Diehl, G. Hasinger, N. Gehrels, C. B. Markwardt, J. Tueller. 2008-08-25. Cosmic X-ray background and Earth albedo Spectra with Swift/BAT. https://doi.org/10.1086/592595

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