TITLE: GCN CIRCULAR NUMBER: 18852 SUBJECT: IPN Triangulation of GRB 151229B (extremely intense/long) DATE: 16/01/11 19:48:08 GMT FROM: Dmitry Svinkin at Ioffe Institute S. Golenetskii, R. Aptekar, D. Frederiks, D. Svinkin, and T. Cline on behalf of the Konus-Wind team, 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, A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo, and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team, S. Barthelmy, J. Cummings, N. Gehrels, H. Krimm, and D. Palmer, on behalf of the Swift-BAT 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, extremely intense GRB 151229B has been detected by Konus-Wind, Swift (BAT), and INTEGRAL (SPI-ACS), so far, at about 77063 s UT (21:24:23). The burst was outside the coded field of view of the BAT. The burst was Mars-occulted to Odyssey. We have triangulated it to a preliminary, 3 sigma error box whose coordinates are: --------------------------------------------- RA(2000), deg Dec(2000), deg --------------------------------------------- Center: 66.759 (04h 27m 02s) -7.167 ( -7d 10' 00") Corners: 71.595 (04h 46m 23s) -10.885 (-10d 53' 06") 67.582 (04h 30m 20s) -8.217 ( -8d 13' 00") 62.910 (04h 11m 38s) -3.557 ( -3d 33' 27") 65.994 (04h 23m 59s) -6.129 ( -6d 07' 46") --------------------------------------------- The error box area is about 3 sq. deg, and its maximum dimension is 11.3 deg (the minimum one is 27 arcmin). The Sun distance was 136 deg. This box may be improved. A triangulation map is posted at http://www.ioffe.ru/LEA/GRBs/GRB151229_T77056/IPN/ The Konus-Wind time history and spectrum will be given in a forthcoming GCN Circular.