Swift/XRT follow up on X-ray burst from SAX J1324.5-63.13

ATel #7947; A. Bahramian, C. O. Heinke (Alberta)
on 24 Aug 2015; 17:55 UT
Credential Certification: Arash Bahramian (bahramia@ualberta.ca)

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Following a MAXI report of an X-ray burst from the vicinity of SAX J1324.5-6313 on Aug 21st (ATel #7943), we observed this region with Swift/XRT in PC mode (Aug 23rd, Obs.ID 35708007). There is only one source significantly detected in this observation, with only 10 counts. The coordinates of this source are consistent with candidate counterpart B from Cornelisse et al. 2002 (A&A,392,931). In previous Swift/XRT observations of this region (Campana 2009, ApJ, 699, 1144), Source B shows an average flux of 7.1(+/-0.8)e-13 erg/s/cm^2 (in 0.5-10 keV). In our new observation, the source is slightly brighter with a flux of 1.4(+/-0.5)e-12 erg/s/cm^2. Assuming a distance of 6 kpc (upper limit indicated to be 6.2 kpc, Cornelisse et al. 2002), this corresponds to a luminosity of 5.6e33 erg/s, consistent with very low-level accretion. This indicates that either the detected bursts in MAXI occurred during very low-level accretion, or that SAX J1324.5-6313 declined very rapidly (~< 2 days) from outburst. We thank the Swift team for rapidly scheduling our observation.