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The Cosmic X-ray Background spectrum observed with ROSAT and ASCA

T. Miyaji·Y. Ishisaki·Y. Ogasaka·Y. Ueda·M. J. Freyberg·G. Hasinger·Y. Tanaka
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Abstract

We have made a series of joint spectral fits for two blank fields, the Lockman Hole and the Lynx-3A field, where a significant amount of both ASCA and ROSAT PSPC data exist after thorough screenings. The ASCA SIS, GIS and ROSAT PSPC spectra from these fields have been fitted simultaneously. Comparison at E>1$keV shows general agreement within 10% in the Lockman Hole data and a 20-30% disagreement in the Lynx-3A data, indicating remaining observation-dependent systematic problems. In both cases, satisfactory fits have been found for the overall 0.1-10 keV spectrum with an extragalactic power-law component (or a broken power-law component with steepening at E<1 keV), a hard thermal component with plasma temperature of kT\approx 0.14 keV and a soft thermal component kT\approx 0.07 keV.

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T. Miyaji, Y. Ishisaki, Y. Ogasaka, Y. Ueda, M. J. Freyberg, G. Hasinger, Y. Tanaka. 1998-03-28. The Cosmic X-ray Background spectrum observed with ROSAT and ASCA. https://arxiv.org/abs/astro-ph/9803320

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