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arXiv · 2108.08039

Investigating the true nature of three hard X-ray sources

Manuela Molina·Angela Malizia·Nicola Masetti·Loredana Bassani·Angela Bazzano·Anthony J. Bird·Mariateresa Fiocchi·Eliana Palazzi·Pietro Ubertini
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Abstract

Many of the new high energy sources discovered both by INTEGRAL/IBIS and Swift/BAT have been characterised thanks to extensive, multi-band follow-up campaigns, but there are still objects whose nature remains to be asserted. In this paper we investigate the true nature of three high energy sources, IGR J12134-6015, IGR J16058-7253 and Swift J2037.2+4151, employing multiwavelength data from the NIR to the X-rays. Through Gaia and ESO-VLT measurements and through Swift/XRT X-ray spectral analysis, we re-evaluate the classification for IGR J12134-6015, arguing that the source is a Galactic object and in particular a Cataclysmic Variable. We were able to confirm, thanks to NuSTAR observations, that the hard X-ray emission detected by INTEGRAL/IBIS and Swift/BAT from IGR J16058-7253 is coming from two Seyfert 2 galaxies which are both counterparts for this source. Through optical and X-ray spectral analysis of Swift J2037.2+4151 we find that this source is likely part of the rare and peculiar class of Symbiotic X-ray binaries and displays flux and spectral variability as well as interesting spectral features, such as a blending of several emission lines around the iron line complex.

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Manuela Molina, Angela Malizia, Nicola Masetti, Loredana Bassani, Angela Bazzano, Anthony J. Bird, Mariateresa Fiocchi, Eliana Palazzi, Pietro Ubertini. 2021-08-18. Investigating the true nature of three hard X-ray sources. https://doi.org/10.1093/mnras%2Fstab2370

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