TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  928
SUBJECT: IPN/RXTE TRIANGULATION OF GRB010126
DATE:    01/01/31 18:34:52 GMT
FROM:    Kevin Hurley at UCBerkeley/SSL  <khurley@sunspot.ssl.berkeley.edu>

K. Hurley, on behalf of the Ulysses GRB team, D. Smith, on behalf
of the RXTE-ASM GRB team, T. Cline, on behalf of the Konus-Wind
and NEAR GRB teams, and E. Mazets and S. Golenetskii, on behalf
of the Konus-Wind GRB team, report:

NEAR observed this event, previously reported in GCN 921 and 922.
Triangulating this burst with Ulysses, Konus, and NEAR gives a
preliminary, 3 sigma error box whose area is ~240 sq. arcmin. 
and whose coordinates are:

    RA(2000)                 DEC(2000)
 11 h 58 m 45.64 s     50 o  2 '  41.37 "  (CENTER)
 12 h  0 m  2.95 s     49 o 59 '   3.02 "  (CORNER)
 12 h  1 m  3.73 s     50 o  5 '  46.18 "  (CORNER)
 11 h 56 m 25.01 s     49 o 59 '  30.17 "  (CORNER)
 11 h 57 m 27.75 s     50 o  6 '  17.68 "  (CORNER)

Although this error box is consistent with the previous triangulations,
it excludes the 90% confidence RXTE-ASM error box, and therefore the
IPN/RXTE error boxes which were based on it.  However, extending the
long dimension of the ASM error box from 1.5 degrees (90% confidence)
to 2.0 degrees (3 sigma) does produce an RXTE-ASM/IPN intersection.
The resulting error box has an area of ~20 sq. arcmin. whose
coordinates are:

    RA(2000)		      DEC(2000)
 11 h 58 m 21.49 s      50 o 02 ' 20.00 " (CENTER)
 11 h 57 m 59.42 s	49 o 59 ' 20.44 " (CORNER)
 11 h 58 m 18.57 s  	49 o 59 ' 18.09 " (CORNER)
 11 h 58 m 40.70 s	50 o 04 ' 38.00 " (CORNER)
 11 h 58 m 27.26 s	50 o 06 ' 04.00 " (CORNER)

A map has been posted at ssl.berkeley.edu/ipn3/010126
showing the new RXTE-ASM error box and its intersection
with the IPN annuli.  (Do not attempt to derive coordinates
from this map, which is a plane projection.)

We regret any confusion caused.