GCN Circular 290

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.