RXTE PCA and Swift BAT detects the Millisecond Pulsar Swift J1756.9-2508 in Outburst
ATel #2129; C. B. Markwardt (U. Maryland and NASA/GSFC), , T. E. Strohmayer (NASA/GSFC), J. H. Swank (NASA/GSFC), S. E. Smith (WIS/NASA/GSFC),D. Pereira (Wyle IS and NASA/GSFC)
on 14 Jul 2009; 20:11 UT
Distributed as an Instant Email Notice Transients
Credential Certification: Alessandro Patruno (a.patruno@uva.nl)
Subjects: X-ray, Request for Observations, Binary, Neutron Star, Transient
Referred to by ATel #: 11981
We report a detection of increased activity of the accreting
millisecond X-ray pulsar Swift J1756.9-2508 observed with the RXTE-PCA
monitoring on July 8, 9hr UTC.
Increased flux is detected simultaneously on the Swift-BAT camera.
RXTE-PCA follow up observations starting on July 13, 23hr UTC,
detected the source in the 2-16 keV band at a flux level of
approximately 19 mCrab, rising to 22 mCrab on July 14, 2hr UTC.
Swift J1756.9-2508 was previously observed in outburst in June 2007 (Atel #1107),
suggesting a recurrence time of approximately 2 years.
Barycentered data at the Swift-XRT position (Krimm et al. 2007)
show a peak in the power density spectrum which is entirely consistent
with the 182.0658 Hz reported by Krimm et al. (2007).
More PCA observations are planned. Follow-up observations at other
wavelengths are encouraged.
