TITLE: GCN CIRCULAR NUMBER: 20475 SUBJECT: IPN Triangulation of GRB 170115B DATE: 17/01/17 08:43:56 GMT FROM: Anna Kozlova 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, 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 long-duration GRB 170115B (Fermi GBM detection: Hamburg et al., GCN 20463) has been detected by Fermi(GBM), Konus-Wind, INTEGRAL (SPI-ACS), and Mars-Odyssey(HEND), so far, at about 64154 s UT (17:49:14). We have triangulated it to a Konus-HEND annulus centered at RA(2000)=171.562 deg (11h 26m 15s) Dec(2000)=+4.317 deg (+4d 19' 01"), whose radius is 53.310 +/- 0.093 deg (3 sigma). This annulus intersects the Fermi-LAT 90% CL error circle (McEnery et al., GCN Circ. 20464) to form an error box whose area is about 2 times smaller than that of the LAT error circle, and whose corners are: ----------------------------------------------- RA(2000), deg Dec(2000), deg ----------------------------------------------- Corners: 189.426 -46.696 189.079 -46.592 188.888 -46.644 188.743 -46.884 ----------------------------------------------- The box area is about 260 sq. arcmin. This box may be improved. A triangulation map is posted at http://www.ioffe.ru/LEA/GRBs/GRB170115_T64155/IPN/ The Konus-Wind time history and spectrum will be given in a forthcoming GCN Circular.