TITLE: GCN CIRCULAR NUMBER: 8132 SUBJECT: Konus-Wind observations of new SGR 0501+4516 DATE: 08/08/25 18:15:54 GMT FROM: Dmitry Frederiks at Ioffe Institute S. Golenetskii, R. Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, P. Oleynik, D. Svinkin, M. Ulanov and T. Cline, on behalf of the Konus-Wind team report: On August 23-25 Konus-Wind detected in triggered mode four bursts from new SGR 0501+4516 (Holland et al. GCN 8112, Barthelmy et al. GCN 8113). First two of these bursts were localized by Swift (Palmer et al. ATel #1678). The others had the same estimated ecliptic latitude, temporal structure and spectral parameters and so we can with great degree of probability attribute them to the new SGR. The burst lightcurves vary from a single pulse with a duration of less than 50 ms to more complex structure lasting for ~500ms. The spectra of the bursts demonstrate a pronounced spectral evolution and are well fitted (in the 20-200 keV range) by the power law with exponential cutoff. The bursts energetics in this range is summarized in the table below. The high values of the peak fluxes, comparable to ones for the strongest recurrent bursts from the other known SGRs may imply the lower distance to the source. -------------------------------------------------------------------- Date UT Fluence Peak flux (2ms) erg/cm2 erg/cm2/s -------------------------------------------------------------------- 080823a 04:47:46.194(*) -- -- 080823b 11:27:32.652 4x10-6 7x10-5 080824 01:17:55.316 2.5x10-5 2x10-4 080825 04:48:27.445 3.3x10-6 1.6x10-4 -------------------------------------------------------------------- (*) data are incomplete at this time The Konus-Wind light curves are available at Ioffe website: http://www.ioffe.ru/LEA/SGRs/080823_T41252/ http://www.ioffe.ru/LEA/SGRs/080824_T04675/ http://www.ioffe.ru/LEA/SGRs/080825_T17307/