TITLE: GCN CIRCULAR NUMBER: 18720 SUBJECT: IPN Triangulation of GRB 151222A (short/hard) DATE: 15/12/24 12:28:19 GMT FROM: Dmitry Svinkin at Ioffe Institute 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, S. Golenetskii, R. Aptekar, V. Pal'shin, D. Frederiks, D. Svinkin, and T. Cline on behalf of the Konus-Wind team, V. Connaughton, M. S. Briggs, C. Meegan, V. Pelassa, and A. Goldstein, on behalf of the Fermi GBM 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 short-duration, hard-spectrum GRB 151222A has been detected by Konus-Wind, Fermi (GBM: Hoi-Fung Yu GCN Circ. 18715), INTEGRAL (SPI-ACS), and Mars-Odyssey (HEND), so far, at about 29414 s UT (08:10:14). We have triangulated it to a preliminary, 3 sigma error box whose coordinates are: --------------------------------------------- RA(2000), deg Dec(2000), deg --------------------------------------------- Center: 354.942 (23h 39m 46s) +34.095 (+34d 05' 44") Corners: 355.188 (23h 40m 45s) +34.534 (+34d 32' 01") 354.558 (23h 38m 14s) +33.943 (+33d 56' 34") 354.701 (23h 38m 48s) +33.652 (+33d 39' 07") 355.328 (23h 41m 19s) +34.244 (+34d 14' 39") --------------------------------------------- The error box area is 792 sq. arcmin, and its maximum dimension is 58 arcmin (the minimum one is 16.8 arcmin). The Sun distance was 98 deg. This box may be improved. A triangulation map is posted at http://www.ioffe.ru/LEA/GRBs/GRB151222_T29415/IPN/ The Konus-Wind time history and spectrum will be given in a forthcoming GCN Circular.