V. D'Elia (SSDC), A. Y. Lien (GSFC/UMBC), K. L. Page (U Leicester),
D. M. Palmer (LANL) and A. Tohuvavohu (PSU) report on behalf of the
Neil Gehrels Swift Observatory Team:
At 03:17:21 UT, the Swift Burst Alert Telescope (BAT) triggered and
located MAXI J1631-479 (trigger=885456). Swift slewed immediately to the target.
The BAT on-board calculated location is
RA, Dec 247.798, -47.808 which is
RA(J2000) = 16h 31m 11s
Dec(J2000) = -47d 48' 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.
The XRT began observing the field at 03:19:14.0 UT, 112.3 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 247.8092, -47.8066 which is equivalent to:
RA(J2000) = 16h 31m 14.21s
Dec(J2000) = -47d 48' 23.8"
with an uncertainty of 5.3 arcseconds (radius, 90% containment),
consistent with the known position of MAXI J1631-479. No event data
are yet available to determine the column density using X-ray spectroscopy.
The initial flux in the 0.1 s image was 3.90e-08 erg cm^-2 s^-1 (0.2-10