IGR J17503-2636: a candidate supergiant fast X-ray transient
Abstract
The object IGR J17503-2636 is a hard X-ray transient discovered by INTEGRAL on 2018 August 11. This was the first ever reported X-ray emission from this source. Following the discovery, follow-up observations were carried out with Swift, Chandra, NICER, and NuSTAR. Here we report on the analysis of all of these X-ray data and the results obtained. Based on the fast variability in the X-ray domain, the spectral energy distribution in the 0.5-80 keV energy range, and the reported association with a highly reddened OB supergiant at ∼10 kpc, we conclude that IGR J17503-2636 is most likely a relatively faint new member of the supergiant fast X-ray transients. Spectral analysis of the NuSTAR data revealed a broad feature in addition to the typical power-law with exponential roll-over at high energy. This can be modeled either in emission or as a cyclotron scattering feature in absorption. If confirmed by future observations, this feature would indicate that IGR J17503-2636 hosts a strongly magnetized neutron star with B ∼ 2 × 1012 G.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- April 2019
- DOI:
- 10.1051/0004-6361/201935185
- arXiv:
- arXiv:1903.03210
- Bibcode:
- 2019A&A...624A.142F
- Keywords:
-
- accretion;
- accretion disks;
- methods: observational;
- binaries: close;
- stars: neutron;
- X-rays: binaries;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- Submitted to A&