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Rossi X-ray Timing Explorer Observations of the X-ray Pulsar EXO 1722-363 - a Candidate Eclipsing Supergiant System

Robin H. D. Corbet·Craig B. Markwardt·Jean H. Swank
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Abstract

Observations made of the X-ray pulsar EXO 1722-363 using the Proportional Counter Array and All Sky Monitor on board the Rossi X-ray Timing Explorer reveal the orbital period of this system to be 9.741 +/- 0.004 d from periodic changes in the source flux. The detection of eclipses, together with the values of the pulse and orbital periods, suggest that this source consists of a neutron star accreting from the stellar wind of an early spectral type supergiant companion. Pulse timing measurements were also obtained but do not strongly constrain the system parameters. The X-ray spectra can be well fitted with a model consisting of a power law with a high energy cutoff and, for some spectra, a blackbody component with a temperature of approximately 0.85 keV.

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Robin H. D. Corbet, Craig B. Markwardt, Jean H. Swank. 2005-07-11. Rossi X-ray Timing Explorer Observations of the X-ray Pulsar EXO 1722-363 - a Candidate Eclipsing Supergiant System. https://doi.org/10.1086/444610

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