TITLE: GCN CIRCULAR NUMBER: 32857 SUBJECT: IPN triangulation of GRB 221022C (short) DATE: 22/10/26 17:33:29 GMT FROM: Dmitry Svinkin at Ioffe Institute D. Svinkin, D. Frederiks, A. Ridnaia, A. Lysenko, and T. Cline on behalf of the Konus-Wind team, A. Goldstein, M. S. Briggs, C. Wilson-Hodge, and E. Burns on behalf of the Fermi GBM team, E. Bozzo and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team, and S. Barthelmy, J. Cummings, H. Krimm, D. Palmer, and A. Tohuvavohu on behalf of the Swift-BAT team, report: The short-duration GRB 221022C (Fermi-GBM detection: Poolakkil and Meegan, GCN Circ. 32836) was detected by Fermi (GBM trigger 688142511), INTEGRAL (SPI-ACS), Konus-Wind, and Swift (BAT) at about 52906 s UT (14:41:46). The burst was outside the coded field of view of the BAT. We have triangulated it to two preliminary, 3 sigma error boxes whose coordinates are: Box 1: --------------------------------------------- RA(2000), deg Dec(2000), deg --------------------------------------------- Center: 231.382 (15h 25m 32s) -57.938 (-57d 56' 16") Corners: 234.870 (15h 39m 29s) -56.438 (-56d 26' 17") 235.716 (15h 42m 52s) -56.321 (-56d 19' 17") 226.200 (15h 04m 48s) -59.592 (-59d 35' 33") 224.388 (14h 57m 33s) -59.790 (-59d 47' 25") --------------------------------------------- Box 2: --------------------------------------------- RA(2000), deg Dec(2000), deg --------------------------------------------- Center: 193.697 (12h 54m 47s) -60.774 (-60d 46' 28") Corners: 189.204 (12h 36m 49s) -59.842 (-59d 50' 33") 188.243 (12h 32m 58s) -59.852 (-59d 51' 09") 200.024 (13h 20m 06s) -61.584 (-61d 35' 03") 201.980 (13h 27m 55s) -61.500 (-61d 29' 58") --------------------------------------------- The error box area is 1.28 sq. deg, and their maximum dimension is 6.91 deg (the minimum one is 12.4 arcmin). The Sun distance was 50 deg. This localization may be improved. The IPN localization is consistent with, but reduces the area of, the Fermi-GBM final localization (glg_healpix_all_bn221022612_v00). A triangulation map and HEALPix FITS file are posted at http://www.ioffe.ru/LEA/GRBs/GRB221022_T52903/IPN The Konus-Wind time history and spectrum will be given in a forthcoming GCN Circular.