TITLE: GCN CIRCULAR NUMBER: 13977 SUBJECT: IPN Triangulation of GRB 121118B (long/intense) DATE: 12/11/20 19:42:38 GMT FROM: Dmitry Svinkin at Ioffe Institute K. Hurley on behalf of the Mars Odyssey and MESSENGER GRB teams, I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin, on behalf of the HEND-Odyssey GRB team, J. Goldsten, on behalf of the MESSENGER GRNS 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, W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr, on behalf of the GRS-Odyssey GRB team, A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo, and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS 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, G. Di Cocco, F. Fuschino, M. Galli, C. Labanti, and M. Marisaldi, on behalf of the AGILE MCAL team, S. Barthelmy, J. Cummings, N. Gehrels, H. Krimm, and D. Palmer, on behalf of the Swift-BAT team, report: The long-duration, intense GRB 121118B was observed by Konus-Wind, INTEGRAL (SPI-ACS), MESSENGER (GRNS), Mars Odyssey (HEND), Swift (BAT), AGILE (MCAL), and Suzaku (WAM), at about 80826 s UT (22:27:06). 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: 171.704 (11h 26m 49s) -3.059 ( -3d 03' 31") Corners: 172.128 (11h 28m 31s) -2.327 ( -2d 19' 38") 170.954 (11h 23m 49s) -4.797 ( -4d 47' 48") 171.309 (11h 25m 14s) -3.726 ( -3d 43' 33") 172.662 (11h 30m 39s) -0.850 ( +0d 51' 00") --------------------------------------------- The error box area is 0.4 sq. deg, and its maximum dimension is 4.3 deg (the minimum one is 1.1 deg, the minimum annulus width is 8.5 arcmin). This box can be improved. The time history and spectrum will be given in a forthcoming GCN Circular.