Resolving the 10-40 keV Cosmic X-ray Background with Constellation-X

TL;DR

This paper discusses how the Constellation-X mission's hard X-ray telescope will significantly improve sensitivity and resolve a substantial portion of the Cosmic X-ray background around 30 keV, a previously unprobed energy range.

Contribution

It introduces the first imaging telescope capable of probing the 10-40 keV X-ray background, enabling resolution of at least 40% of this energy range.

Findings

Constitution-X will improve sensitivity by several orders of magnitude.

It will resolve at least 40% of the 10-40 keV XRB.

First imaging in this energy range will be achieved.

Abstract

The energy density of the Cosmic X-ray background (XRB) peaks around 30 keV (see Figure 1), an energy not yet probed by focussing imaging instruments. The first hard X-ray telescope due to fly on a space mission will be that on board Constellation-X. The imaging capability, besides providing an improvement of several orders of magnitude in sensitivity over current passively collimated detectors, will permit for the first time to resolve a fraction of the XRB at this most crucial energy. Synthesis models of the XRB based on obscured AGN predict that at least 40% of the 10-40 keV XRB will be resolved by Constellation-X.