N ov 2 00 3 Periodic Optical Outbursts from the Be / Neutron Star Binary AX J 0049 . 4 − 7323
نویسندگان
چکیده
The optical light curve of the Be/neutron star binary AX J0049.4−7323 has been investigated using data from the MACHO and OGLE-II projects. This X-ray source, whose neutron star has a very slow rotation rate (P pulse = 755.5 sec), shows optical outbursts every ∼394 days. The regularity of these outbursts suggests that their recurrence time is the orbital period of the system. During the outbursts the system brightens and becomes slightly redder. A possible interpretation is that a portion of the equatorial disk is excited as the neutron star passes through it during periastron passage. In the intervals between outbursts the light curve shows ∼11-day quasi-periodic varability which may be associated with the rotation of the Be star's extended disk.
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