Swift follow-up of 13 INTEGRAL sources

TL;DR

This study used Swift X-ray observations to precisely locate 13 INTEGRAL sources, enabling identification of their counterparts at other wavelengths and providing insights into their nature.

Contribution

The paper presents the first precise X-ray positions for 13 INTEGRAL sources using Swift, facilitating multi-wavelength counterpart identification and source classification.

Findings

Possible counterparts found for all 13 sources.

Infrared, optical, and UV counterparts identified.

Enhanced positional accuracy aids in source classification.

Abstract

Abridged : The various IBIS/ISGRI catalogues contain a large population of hard X-ray sources whose nature is still unknown. Even if the $>20$ keV positional uncertainty provided by ISGRI is unprecedented, it is still too large to pinpoint the counterpart at other wavelengths, which is the only secure way of obtaining a source identification. We continue the work of trying to reveal the nature of these hard X-ray sources, starting with analysis of X-ray data collected via focusing X-ray telescopes, in order to obtain arcsec accurate X-ray positions. We can then identify counterparts at infrared and optical wavelengths and try to unveil the nature of the sources. We analysed data from observations of 13 \integral\ sources made with the \swift\ satellite. The X-ray images obtained by the X-Ray Telescope instrument allowed us to find possible counterparts to the IGR sources with a positional accuracy of a few arcsec. We then browsed the online catalogues to search for counterparts at other wavelengths. We also made use of the X-ray spectral parameters in trying to identify the nature of those objects. For the 13 objects, we found possible counterparts at X-ray energies and identified the IR/optical and/or UV counterparts as seen with \swift/UVOT. We also discuss the likelihood of association of the X-ray and \integral\ source in each case.