TITLE:   GCN CIRCULAR
NUMBER:  22263
SUBJECT: IPN Triangulation of GRB 171216B
DATE:    17/12/20 05:26:15 GMT
FROM:    Anna Kozlova at Ioffe Institute  <ann_kozlova@mail.ioffe.ru>

K. Hurley, on behalf of the IPN,

I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin,
on behalf of the HEND-Odyssey GRB team,

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

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

W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr,
on behalf of the GRS-Odyssey GRB team, report:

The long-duration GRB 171216B was detected
by Konus-Wind, INTEGRAL (SPI-ACS), CALET (CGBM), and
Mars-Odyssey (HEND) at about 51947 s UT (14:25:47).

We have triangulated it to a preliminary, 3 sigma error box whose 
coordinates are:
  ---------------------------------------------
   RA(2000), deg                 Dec(2000), deg
  ---------------------------------------------
  Center:
   340.068 (22h 40m 16s) +52.048 (+52d 02' 54")
  Corners:
   340.072 (22h 40m 17s) +51.848 (+51d 50' 54")
   339.877 (22h 39m 30s) +51.992 (+51d 59' 32")
   340.064 (22h 40m 15s) +52.248 (+52d 14' 54")
   340.259 (22h 41m 02s) +52.104 (+52d 06' 15")
  ---------------------------------------------
The error box area is 170 sq. arcmin, and its maximum
dimension is 24 arcmin (the minimum one is 10.0 arcmin).
The Sun distance was 100 deg.

This box may be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB171216_T51948/IPN

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