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GCN Circular 23639

Trigger 882561: Swift detection of MAXI J1631-479
2019-01-08T01:44:16Z (5 years ago)
David Palmer at LANL <>
S. D. Barthelmy (GSFC), C. Gronwall (PSU), J. A. Kennea (PSU),
H. A. Krimm (NSF/USRA), D. M. Palmer (LANL) and A. Tohuvavohu (PSU)
report on behalf of the Neil Gehrels Swift Observatory Team:

At 01:21:53 UT, the Swift Burst Alert Telescope (BAT) triggered and
located the new source MAXI J1631-479 (trigger=882561).  Swift did not slew
due an observing constraint.  The BAT on-board calculated location is 
RA, Dec 247.810, -47.725, which is 
   RA(J2000)  =  16h 31m 14s
   Dec(J2000) = -47d 43' 28"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  As is typical for an image trigger, there is nothing
visible in the real-time light curve. 

We confirm that Trigger 878548 on 2018-12-23 (D'Avanzo et al. 
GCN #23550) was also due to MAXI J1631-479 as reported by 
Miyasaka et al. (ATel #12340).   BAT has been detecting this 
source continuously since discovery. 

XRT and UVOT observations are planned for when this
source comes out of Sun constraint around January 14.
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