[vsnet-grb-info 16744] Trigger 649143: Swift detection of AX J1619.4-4945

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18025
SUBJECT: Trigger 649143: Swift detection of AX J1619.4-4945
DATE:    15/07/16 02:40:41 GMT
FROM:    David Palmer at LANL  <palmer at lanl.gov>

S. D. Barthelmy (GSFC), J. A. Kennea (PSU), P. Romano (INAF-IASFPA)
and B. Sbarufatti (INAF-OAB/PSU) report on behalf of the Swift Team:

At 01:54:25 UT, the Swift Burst Alert Telescope (BAT) triggered and
located AX J1619.4-4945 (trigger=649143).  Swift's slew was delayed
by an SAA transit and lack of observability. 
The BAT on-board calculated location is 
RA, Dec 244.970, -49.810 which is 
   RA(J2000)  =  16h 19m 53s
   Dec(J2000) = -49d 48' 35"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  As is typical with image triggers,
there is nothing significant in the real-time light curve. 

Although we believe that this is probably the HMXB source
AX J1619.4-4945, the marginal significance (6.46 sigma)
and distance from the catalog position (5 arcminutes)
leave some room for doubt.  Confirmation of this detection
will require the full downlinked dataset and follow-up
observations by XRT.