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arXiv · 2307.04238

Measuring the Cosmic X-ray Background accurately

Hancheng Li·Roland Walter·Nicolas Produit·Fiona Hubert
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Abstract

Synthesis models of the diffuse Cosmic X-ray Background (CXB) suggest that it can be resolved into discrete sources, primarily Active Galactic Nuclei (AGNs). Measuring the CXB accurately offers a unique probe to study the AGN population in the nearby Universe. Current hard X-ray instruments suffer from the time-dependent background and cross-calibration issues. As a result, their measurements of the CXB normalization have an uncertainty of the order of $\sim$15%. In this paper, we present the concept and simulated performances of a CXB detector, which could be operated on different platforms. With a 16-U CubeSat mission running for more than two years in space, such a detector could measure the CXB normalization with $\sim$1% uncertainty.

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Hancheng Li, Roland Walter, Nicolas Produit, Fiona Hubert. 2023-07-09. Measuring the Cosmic X-ray Background accurately. https://doi.org/10.1007/s10686-023-09896-7

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