TITLE:   GCN CIRCULAR
NUMBER:  22423
SUBJECT: IPN Triangulation of GRB 180218A (long/bright)
DATE:    18/02/19 16:54:13 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

D.Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, A. Kozlova,
and T. Cline on behalf of the Konus-Wind team,

K. Hurley, on behalf of the IPN,

V. Connaughton, M. S. Briggs, C. Meegan, V. Pelassa,
and A. Goldstein, on behalf of the Fermi GBM team, and

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team, report:

The long-duration, very bright GRB 180218A has been detected by
Fermi(GBM; trigger 540659650), Konus-Wind, INTEGRAL(SPI-ACS), and 
Swift(BAT) at about 54845 s UT (15:14:05). The burst was outside the 
coded field of view of the BAT.

We have triangulated it to a preliminary, 3 sigma error box whose 
coordinates are:
---------------------------------------------
   RA(2000), deg                 Dec(2000), deg
  ---------------------------------------------
  Center:
    46.279 (03h 05m 07s) +52.589 (+52d 35' 20")
  Corners:
    49.798 (03h 19m 12s) +45.859 (+45d 51' 34")
    50.993 (03h 23m 58s) +46.050 (+46d 03' 00")
    41.217 (02h 44m 52s) +59.126 (+59d 07' 35")
    39.654 (02h 38m 37s) +58.828 (+58d 49' 40")
  ---------------------------------------------
The error box area is 12.13 sq. deg, and its maximum
dimension is 14.48 deg (the minimum one is 51 arcmin).
The Sun distance was 89 deg.

This box may be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB180218_T54845/IPN/

The time history and spectrum will be given in forthcoming
GCN Circulars.