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arXiv · 1712.00096

Identification of two new HMXBs in the LMC: a $\sim$2013 s pulsar and a probable SFXT

G. Vasilopoulos·C. Maitra·F. Haberl·D. Hatzidimitriou·M. Petropoulou
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Abstract

We report on the X-ray and optical properties of two high-mass X-ray binary systems located in the Large Magellanic Cloud (LMC). Based on the obtained optical spectra, we classify the massive companion as a supergiant star in both systems. Timing analysis of the X-ray events collected by XMM-Newton revealed the presence of coherent pulsations (spin period $\sim$2013 s) for XMMU J053108.3-690923 and fast flaring behaviour for XMMU J053320.8-684122. The X-ray spectra of both systems can be modelled sufficiently well by an absorbed power-law, yielding hard spectra and high intrinsic absorption from the environment of the systems. Due to their combined X-ray and optical properties we classify both systems as SgXRBs: the 19$^{\rm th}$ confirmed X-ray pulsar and a probable supergiant fast X-ray transient in the LMC, the second such candidate outside our Galaxy.

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G. Vasilopoulos, C. Maitra, F. Haberl, D. Hatzidimitriou, M. Petropoulou. 2017-12-10. Identification of two new HMXBs in the LMC: a $\sim$2013 s pulsar and a probable SFXT. https://doi.org/10.1093/mnras%2Fstx3139

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