Pulsar EXO 1722 - 363 - a Candidate Eclipsing Supergiant System
نویسندگان
چکیده
Observations made of the X-ray pulsar EXO1722-363 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. Subject headings: stars: individual (EXO1722-363) — stars: neutron — X-rays: stars
منابع مشابه
Spectral classification of the mass donors in the high - mass X - ray binaries EXO 1722 - 363 and OAO 1657 - 415 . ⋆
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