Swift/BAT observations of IGR J15791-2342
ATel #11981; H. A. Krimm (NSF/USRA), S. D. Barthelmy (GSFC), J. R. Cummings (CPI), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i. e. the Swift-BAT team), L. Ducci (IAAT, Germany; ISDC, Switzerland), E. Bozzo (ISDC, Switzerland)
on 23 Aug 2018; 17:38 UT
Credential Certification: Hans A. Krimm (hkrimm@nsf.gov)
Subjects: X-ray, Binary, Neutron Star, Transient, Pulsar
Examination of archival data from the Neil Gehrels Swift Observatory Burst Alert Telescope (Swift/BAT) shows that the accreting millisecond pulsar IGR J15791-2342, discovered by INTEGRAL (Ducci et al., ATel #11941, Bozzo et al., ATel #11942, Ferrigno et al., ATel #11957), was detected in the BAT transient monitor in the 15-150 keV band between 2018-July-22 and 2018-Aug-19 (MJD 58320-58349), starting 20 days before the INTEGRAL discovery. The count rate was 0.0067 +/- 0.0013 ct/cm2/s (~30 mCrab; MJD 58320), peaked at 0.011 +/ 0.0014 ct/cm2/s (~50 mCrab; MJD 58324) and was detected at 0.0040 +/- 0.0009 ct/cm2/s (~18 mCrab; MJD 58340 = 2018-Aug-10, the date of the INTEGRAL discovery) and at 0.0048 +/- 0.0011 ct/cm2/s (~22 mCrab; MJD 58349). The peak rate and duration are roughly consistent with those of the accreting millisecond pulsar, Swift J1756.9-2508 (Krimm et al, ApJL 668, 147, 2007; ATel #11497; ATel #2129).
The source was not in the INTEGRAL field of view for the ~20 days prior to the INTEGRAL detection on MJD 58340, except for MJD 58334, when it was at the edge of the ISGRI field of view, and thus not detected.
Swift/BAT Transient Monitor observations of IGRJ17591-2342
