TITLE: GCN CIRCULAR NUMBER: 22051 SUBJECT: IPN Triangulation of GRB 171022A DATE: 17/10/26 18:03:20 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, A. Kozlova, S. Golenetskii, R. Aptekar, D. Frederiks, D. Svinkin, 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, V. Connaughton, M. S. Briggs, C. Meegan, V. Pelassa, and A. Goldstein, on behalf of the Fermi GBM 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 171022A (Fermi-LAT detection: Palatiello et al., GCN Circ. 22045; Fermi-GBM detection: Hamburg and Meegan, GCN Circ. 22046) was detected by Fermi (GBM trigger 530399665), Konus-Wind, INTEGRAL (SPI-ACS), and Mars-Odyssey (HEND) at about 76461 s UT (21:14:21). We have triangulated it to a preliminary, 3 sigma error box whose coordinates are: --------------------------------------------- RA(2000), deg Dec(2000), deg --------------------------------------------- Center: 215.353 (14h 21m 25s) +12.844 (+12d 50' 37") Corners: 217.045 (14h 28m 11s) +1.841 ( +1d 50' 29") 211.510 (14h 06m 02s) +21.802 (+21d 48' 06") 210.607 (14h 02m 26s) +22.804 (+22d 48' 14") 216.812 (14h 27m 15s) +3.167 ( +3d 10' 03") --------------------------------------------- The error box area is 4.1 sq. deg, and its maximum dimension is 21.9 deg (the minimum one is 12.0 arcmin). The Sun distance was 16 deg. This box may be improved. The Fermi (LAT) on-ground location (RA, Dec, Rerr = 204.28, 10.98, 0.16 deg) reported in Palatiello et al. is inconsistent with the box, the minimum distance between the box and the Fermi (LAT) location is ~11 deg. A triangulation map is posted at http://www.ioffe.ru/LEA/GRBs/GRB171022_T76456/IPN The Konus-Wind time history and spectrum will be given in a forthcoming GCN Circular.