X-Ray Pulsar XTE J1858+034: Discovery of the Cyclotron Line and the Revised Optical Identification



: Tsygankov Sergey S., Lutovinov Alexander A., Molkov Sergey V., Djupvik Anlaug A., Karasev Dmitri I., Doroshenko Victor, Mushtukov Alexander A., Malacaria Christian, Kretschmar Peter, Poutanen Juri

Publisher: IOP PUBLISHING LTD

: 2021

: Astrophysical Journal

: ASTROPHYSICAL JOURNAL

: ASTROPHYS J

: ARTN 154

: 909

: 2

: 10

: 0004-637X

: 1538-4357

DOI: https://doi.org/10.3847/1538-4357/abddbd

: https://iopscience.iop.org/article/10.3847/1538-4357/abddbd

: https://research.utu.fi/converis/portal/detail/Publication/53689812


We present the results of a detailed investigation of the poorly studied X-ray pulsar (XRP) XTE J1858+034 based on the data obtained with the NuSTAR observatory during the outburst of the source in 2019. The spectral analysis resulted in the discovery of a cyclotron absorption feature in the source spectrum at similar to ~48 keV in both the pulse phase-averaged and resolved spectra. Accurate X-ray localization of the source using the NuSTAR and Chandra observatories allowed us to accurately determine the position of the X-ray source and identify the optical companion of the pulsar. The analysis of the counterpart properties suggested that the system is likely a symbiotic binary hosting an XRP and a late-type companion star of the K-M classes rather than a Be X-ray binary as previously suggested.

Last updated on 2024-26-11 at 15:55