GRB 991221

K. Hurley, on behalf of the Ulysses GRB team, T. Cline, on behalf
of the NEAR and KONUS GRB teams, and E. Mazets and S. Golenetskii,
on behalf of the KONUS GRB team, report:

Ulysses, KONUS-WIND, and NEAR observed a relatively bright
(25-100 keV fluence ~1.3 x 10^-5 erg/cm^2), ~60 s long gamma-ray
burst at 38196 s U.T. on December 21 1999.  Triangulation gives
two possible preliminary ~190 sq. arcmin. error boxes whose corners
are at:

  RA(2000)                  DEC(2000)               
14 h 43 m 59.59 s    -42 o 46 '  36.00 "     
14 h 44 m 12.73 s    -43 o 15 '  32.42 "     
14 h 43 m 10.52 s    -42 o 15 '  27.97 "     
14 h 43 m 25.10 s    -42 o 45 '  15.18 " 

             and 
   
  RA(2000)                  DEC(2000)
13 h 54 m  7.11 s    -11 o 41 '  32.68 "
13 h 52 m 58.96 s    -11 o 17 '  47.08 "
13 h 55 m  0.20 s    -12 o 11 '  15.04 "
13 h 53 m 50.77 s    -11 o 46 '  37.87 "

Receipt of the full KONUS data set tomorrow should allow us
to resolve the ambiguity between the two.  Further refinement
of the error boxes is also possible.

P. Butterworth, T. Cline, E. Mazets, and S. Golenetskii, on behalf
of the KONUS-WIND and NEAR GRB Teams, and K. Hurley, on behalf of the Ulysses
GRB team, report:

Analysis of count rates in the north- and south-ecliptic facing KONUS-WIND
detectors clearly indicates that GRB991221 came from the first error
box cited in GCN 507
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 :


  RA(2000)                  DEC(2000)               
14 h 43 m 59.59 s    -42 o 46 '  36.00 "     
14 h 44 m 12.73 s    -43 o 15 '  32.42 "     
14 h 43 m 10.52 s    -42 o 15 '  27.97 "     
14 h 43 m 25.10 s    -42 o 45 '  15.18 " 

This error box can be refined.