Cross-match between the latest Swift-BAT and Fermi-LAT catalogs

TL;DR

This study cross-matched the latest Swift-BAT and Fermi-LAT catalogs, identifying 132 point-like sources and revealing their characteristics, which enhances understanding of sources in the intermediate energy gamma-ray domain.

Contribution

It provides the first comprehensive cross-match between the latest hard X-ray and GeV gamma-ray catalogs, highlighting source populations and their properties.

Findings

132 sources matched, including ~5% false matches

Matched sources are mainly blazars, pulsars, and radio galaxies

Matched sources show higher flux and variability than original catalogs

Abstract

We report the results of a cross-match study between the hard X-ray and GeV gamma-ray catalogs, by making use of the latest 105-month Swift-BAT and 10-yr Fermi-LAT catalogs, respectively. The spatial cross-matching between the two catalogs results in the matching of 132 point-like sources, including ~5% of false-match sources. Additionally, 24 sources that have been identified as the same identifications are matched. Among the 75 extended sources in the Fermi-LAT catalog, 31 sources have spatial coincidences with at least one Swift-BAT source inside their extent. All the matched sources consist of blazars (>60%), pulsars and pulsar wind nebulae (~13%), radio galaxies (~7%), binaries (~5%), and others. Compared to the original catalogs, the matched sources are characterized by a double-peaked photon index distribution, higher flux, and larger gamma-ray variability index. This difference arises from the different populations of sources, particularly the large proportion of blazars (i.e., FSRQ and BL Lac). We also report 13 cross-matched and unidentified sources. The matched sources in this study would be promising in the intermediate energy band between the hard X-ray and GeV gamma-ray observations, that is the unexplored MeV gamma-ray domain.