TITLE: GCN CIRCULAR NUMBER: 30803 SUBJECT: IPN triangulation of a bright burst from SGR 1935+2154 DATE: 21/09/10 20:59:57 GMT FROM: Anna Ridnaia at Ioffe Institute <ridnaia@mail.ioffe.ru> A. Ridnaia, S. Golenetskii, D. Frederiks, D. Svinkin, and T. Cline on behalf of the Konus-Wind team, K. Hurley, on behalf of the IPN, A. Goldstein, M. S. Briggs, and C. Wilson-Hodge on behalf of the Fermi-GBM team, and S. Barthelmy, J. Cummings, H. Krimm, D. Palmer, and A. Tohuvavohu on behalf of the Swift-BAT team, report: A bright, short-duration, soft burst has been observed by Fermi (GBM), Konus-Wind, and Swift (BAT), so far, at about 2747 s UT (00:45:47) on September 10. The burst was outside the coded field of view of the BAT. We have triangulated it to a Konus-GBM annulus centered at RA(2000)=326.594 deg (21h 46m 22s) Dec(2000)=-14.741 deg (-14d 44' 28"), whose radius is 48.801 +/- 0.199 deg (3 sigma). This localization may be improved. The position of SGR 1935+2154 lies inside the annulus at 0.7 arcmin from its center line. Given the positional coincidence of this burst with SGR 1935+2154, its time history, softness of its spectrum (as observed by Konus-Wind), and reported bursting activity (Xiao et al., GCN Circ. 30797), we conclude this burst is likely originated from SGR 1935+2154. A triangulation map is posted at http://www.ioffe.ru/LEA/SGRs/210910_T02750/IPN/ The time history and spectrum will be given in forthcoming GCN Circulars.