SWIFT Detection of a 65-Day X-ray Period from the Ultraluminous Pulsar NGC 7793 P13

Understand

NGC 7793 P13 is an ultraluminous X-ray source harboring an accreting pulsar.

• We report on the detection of a ~65 d period X-ray modulation with Swift observations in this system.
• The modulation period found in the X-ray band is P=65.05+/-0.10 d and the profile is asymmetric with a fast rise and a slower decay.
• On the other hand, the u-band light curve collected by Swift UVOT confirmed an optical modulation with a period of P=64.24+/-0.13 d.