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Timing and spectral studies of the transient X-ray pulsar EXO 053109-6609.2 with ASCA and Beppo-SAX

B. Paul·S. N. A. Jaaffery·S. Naik·P. C. Agrawal
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Abstract

We report timing and spectral properties of the transient Be X-ray pulsar EXO 053109--6609.2 studied using observations made with the ASCA and BeppoSAX observatories. Though there must have been at least one spin-down episode of the pulsar since its discovery, the new pulse period measurements show a monotonic spin-up trend since 1996. The pulse profile is found to have marginal energy dependence. There is also evidence for strong luminosity dependence of the pulse profile, a single peaked profile at low luminosity that changes to a double peaked profile at high luminosity. This suggests a change in the accretion pattern at certain luminosity level. The X-ray spectrum is found to consist of a simple power-law with photon index in the range of 0.4--0.8. At high intensity level the spectrum also shows presence of weak iron emission line.

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B. Paul, S. N. A. Jaaffery, S. Naik, P. C. Agrawal. 2004-02-05. Timing and spectral studies of the transient X-ray pulsar EXO 053109-6609.2 with ASCA and Beppo-SAX. https://doi.org/10.1086/381161

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