TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2823 SUBJECT: Bright bursts from SGR1806-20 DATE: 04/10/19 13:27:31 GMT FROM: Dmitry Frederiks at Ioffe Institute S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks on behalf of Konus-Wind and Helicon/Coronas-F teams, T. Cline on behalf of the Konus-Wind team, and A. Rau, A. von Kienlin, G. Lichti on behalf of the INTEGRAL SPI-ACS GRB team report: Two bright SGR-like events were detected by Konus-Wind on October 16 at 66284.062s UT and October 17 at 23771.551s UT. Both events were also detected by INTEGRAL SPI-ACS, Wind-INTEGRAL triangulation gives the following annuli: The first event: Alpha = 191.74323 Delta =-17.37563 Radius = 75.32431 +/-0.37658 The annulus passes 0.021 deg (0.17 sigma) from SGR 1806-20. The second event: Alpha = 191.85595 Delta =-16.48234 Radius = 75.45488 +/- 0.27746 The annulus passes 0.053 deg (0.57 sigma) from SGR 1806-20. According to the Konus-Wind data the first event on 041016 had a duration of 0.12 sec, fluence 6.4x10-6 erg cm-2, and peak flux 8.5x10-5 erg cm-2 s-1, both in 20-200 keV range. OTTB fit gives parameter kT = 26.5 +/- 1.5 keV The 041017 event had a duration of main pulse of 1.6 sec, fluence 6.5x10-5 erg cm-2, and peak flux 6.7x10-5 erg cm-2 s-1, both in 20-200 keV range. A considerable spectral evolution was observed, OTTB fit gives the following values of kT during event: ------------------------------------ Time after trigger kT sec keV ------------------------------------ 0 - 0.256s 24.1 +/- 0.5 0.256 - 0.768s 20.4 +/- 0.5 0.768 - 1.6s 17.5 +/- 0.7 ------------------------------------ Following the main pulse there were two weaker events (times are given after the trigger), at +11.287 s (fluence ~2x10-7 erg cm-2) and at +157.2s (fluence ~4.5x10-7 erg cm-2).