INTEGRAL 11-year hard X-ray survey above 100 keV

TL;DR

This paper presents an 11-year all-sky survey above 100 keV using INTEGRAL/IBIS, cataloging 132 sources including AGNs, X-ray binaries, and pulsars, with detailed analysis of source properties and distributions.

Contribution

It provides the first comprehensive 11-year hard X-ray survey above 100 keV, including a catalog of sources and analysis of their spectral and spatial characteristics.

Findings

Detected 132 sources in total, with 88 above 5 sigma significance.

Identified 25 sources in the 150-300 keV band, including AGNs and X-ray binaries.

Analyzed source distributions, hardness ratios, and flux relations.

Abstract

We present results of all sky survey, performed with data acquired by the IBIS telescope onboard the INTEGRAL observatory over eleven years of operation, at energies above 100 keV. A catalogue of detected sources includes 132 objects. The statistical sample detected on the time-averaged 100-150 keV map at a significance above 5 sigma contains 88 sources: 28 AGNs, 38 LMXBs, 10 HMXBs and 12 rotation-powered young X-ray pulsars. The catalogue includes also 15 persistent sources, which were registered with the significance 4 sigma < S/N < 5 in hard X-rays, but at the same time were firmly detected (>12 sigma) in the 17-60 keV energy band. All sources from these two groups are known X-ray emitters, that means that the catalogue has 100% purity in respect to them. Additionally, 29 sources were found in different time intervals. In the context of the survey we present a hardness ratio of galactic and extragalactic sources, a LMXBs longitudinal asymmetry and a number-flux relation for non-blazar AGNs. At higher energies, in the 150-300 keV energy band, 25 sources have been detected with a signal-to-noise ratio S/N > 5 sigma, including 7 AGNs, 13 LMXBs, 3 HMXBs, and 2 rotation-powered pulsars. Among LMXBs and HMXBs we identified 12 black hole candidates (BHC) and 4 neutron star (NS) binaries.