Swift/BAT detects hard X-ray emission from RX J0520.5-6932
ATel #5675; H. A. Krimm (CRESST/GSFC/USRA), S. D. Barthelmy (GSFC), W. Baumgartner (CRESST/GSFC/UMBC), J. Cummings (CRESST/GSFC/UMBC), N. Gehrels (GSFC), A. Y. Lien (NASA/GSFC/ORAU), C. B. Markwardt (GSFC), D. Palmer (LANL), T. Sakamoto (Aoyama Gakuin Univ.), M. Stamatikos (OSU/GSFC), T. Ukwatta (MSU)
on 19 Dec 2013; 21:28 UT
Credential Certification: Hans A. Krimm (Hans.Krimm@nasa.gov)
Subjects: X-ray, Binary, Neutron Star, Transient, Pulsar
The Be/X-ray binary RX J0520.5-6932 has been detected in the 15-50 keV band in the Swift/BAT hard X-ray transient monitor. The source was detected in the BAT monitor starting on 2013 December 18 (MJD 56644) with a count rate of 0.003 +/- 0.0005 ct/s/cm^2 (~14 mCrab). Archival data was searched back to the beginning of 2013 and no other time intervals (on the time scale of one day) were found with a significant rate increase above background. There have been four sub-threshold detections onboard Swift/BAT in 2009, 2011, 2013 and most recently on 2013 December 18 at 07:31:16.592 UT.
The source was confirmed as a Be/X-ray binary by Vasilopoulos et al. (ATel #4748) and more recently was seen to be in outburst in Swift/XRT (Vasilopoulos et al., ATel #5673) starting on 2013 December 18. The source was detected by BATSE during an April 1995 outburst using the earth-occultation technique (Edge et al. 2004, MNRAS 349, 1361). The peak BATSE flux at that time was ~20 mCrab.
Swift/BAT transient monitor light curve for RX J0520.5-6932
