TITLE:   GCN CIRCULAR
NUMBER:  14278
SUBJECT: IPN triangulation of GRB 130228A
DATE:    13/03/09 00:08:01 GMT
FROM:    Kevin Hurley at UCBerkeley/SSL  <khurley@ssl.berkeley.edu>

K. Hurley and J. Goldsten, on behalf of the MESSENGER GRB team,

S. Golenetskii, R. Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, D.
Svinkin, and T. Cline on behalf of the Konus-Wind team,

D. M. Smith, J. McTiernan, R. Schwartz, and W. Hajdas, on behalf of the
RHESSI GRB team,

K. Yamaoka, M. Ohno, Y. Hanabata, Y. Fukazawa, T. Takahashi, M.
Tashiro, Y. Terada, T. Murakami, and K. Makishima on behalf of the
Suzaku WAM team,

S. Barthelmy, J. Cummings, N. Gehrels, H. Krimm, and D. Palmer, on
behalf of the Swift-BAT team, and

V. Connaughton, M. S. Briggs, C. Meegan, V. Pelassa, A. von Kienlin,
and A. Rau, on behalf of the Fermi GBM team, report:

GRB 130228A was detected by the Fermi GBM (trigger 383712005),
Konus-Wind, RHESSI, Suzaku WAM, Swift BAT (outside the coded FoV),
and MESSENGER GRNS.  We have triangulated it to a preliminary,
3 sigma error box whose coordinates are:


      	      RA(2000)			      Dec(2000)
Center:  256.8792 = 17 h 07 m 31 s	+57.9767 = 57 d 58 m 36 s
Corners: 257.9210 = 17 h 11 m 41 s	+74.5340 = 74 d 32 m 03 s
         256.9529 = 17 h 07 m 49 s      +36.0592 = 36 d 03 m 33 s
         255.7015 = 17 h 02 m 48 s      +76.3736 = 76 d 22 m 25 s
         256.3030 = 17 h 05 m 13 s      +38.7303 = 38 d 43 m 49 s

and whose area is 22.7 sq. deg.  This error box may be improved.

The minimum distance between the edge of the error box and the
edge of the 0.5 degree radius LAT error circle (Zheng and Akerlof,
GCN 14258) is about 1.5 arcminutes.  Thus the two localizations
are consistent if the LAT error circle radius is a roughly one
sigma confidence region.

Maps have been posted at ssl.berkeley.edu/ipn3/130228.