1A 1118-61: detection of the pulsation period in Swift-XRT data
ATel #1896; Vanessa Mangano (INAF-IASF PA)
on 9 Jan 2009; 15:32 UT
Credential Certification: Vanessa Mangano (vanessa@ifc.inaf.it)
Subjects: X-ray, Binary, Neutron Star, Transient, Pulsar
Referred to by ATel #: 1949
The Be/X-ray transient 1A 1118-61 triggered Swift
on 2009 January 4 at 03:52:35.6 UT (Mangano et al.,
GCN Circ. #8777) and at 13:37:39.6 UT.
The source was monitored by XRT for 4 days,
and a total exposure of 26 ks of data were collected
(17 ks in Windowed Timing mode and 9 ks in Photon Counting mode).
The light curve is highly variable.
We performed a temporal analysis with epoch folding search
techniques around the expected pulsation period of 405 s
(Nagase F. 1989, Publ. Astron. Soc. Jap., 41, 1-79)
and detected a highly significant pulsation at 407.68 +/- 0.02 s.
The folded light curve shows a complex structure with three main
sub-peaks. Further analysis is ongoing.
