GCN Circular 290
Subject
IPN localization for GRB990506
Date
1999-05-06T20:28:10Z (25 years ago)
From
Kevin Hurley at UCBerkeley/SSL <khurley@sunspot.ssl.berkeley.edu>
K. Hurley, on behalf of the Ulysses GRB team, and Scott Barthelmy, on behalf of
the GCN team, report:
We have obtained a preliminary IPN annulus for GRB990506 (BATSE #7549)
using coarse time resolution BATSE/GCN and Ulysses data. This annulus
is refined with respect to that in the GCN/IPN Notice sent out at
19:14:36 UT. The annulus is centered at RA(2000)= 144.960 degrees,
Decl(2000)=-7.324 degrees, and has a radius of 37.424 +/- 0.035 degrees
(3 sigma). It intersects both the BATSE Locburst location for this
burst as well as the RXTE PCA source location sent out today at
17:27:37 UT. The latter intersection defines an ~4' wide by 1 degree
long error box whose corners are:
RA(2000) DEC(2000)
11 h 54 m 23.69 s -26 o 57 ' 59 "
11 h 56 m 15.28 s -26 o 03 ' 34 "
11 h 54 m 06.48 s -26 o 56 ' 11 "
11 h 55 m 58.07 s -26 o 01 ' 50 "
Thus if the RXTE PCA source is found to be fading, it is quite
likely to be the X-ray afterglow of the GRB.
An image may be found at http://ssl.berkeley/edu/ipn3/990506. The IPN annulus
can be refined considerably.