TITLE: GCN CIRCULAR NUMBER: 45924 SUBJECT: Konus-Wind detection of GRB 261011A DATE: 26/10/12 15:15:46 GMT FROM: Anna Ridnaia at Ioffe Institute A. Ridnaia, D. Frederiks, A. Lysenko, V. Panteleeva, D. Svinkin, A. Tsvetkova, M. Ulanov, and T. Cline, on behalf of the Konus-Wind team, report: The long-duration GRB 261011A (SVOM detection: Huang et al., GCN 45895; Swift detection: Cenko et al., GCN 45896) was detected by Konus-Wind (KW) in the waiting mode at about T0 = T0 (SVOM) = 49747 s UT (13:49:07). A Bayesian block analysis of the KW waiting mode data in the 20-400 keV band reveals a ~20 sigma count rate increase in the interval from T0+1.7 s to T0+66.468 s. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB261011A/ The total burst fluence is 1.30(-0.21,+0.62)x10^-5 erg/cm^2, and the 2.944 s peak energy flux, measured from T0+10.532 s, is 4.63(-4.27,+4.74)x10^-7 erg/cm^2/s. (both in the 20 keV - 10 MeV energy range). The time-integrated spectrum of the burst, measured from T0+1.7 s to T0+66.468 s, can be described by a power law with exponential cutoff (CPL) model dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) with alpha = -1.8(-0.1,+0.2) and Ep = 198(-67,+869) keV. All the quoted errors are estimated at the 68% confidence level. All the presented results are preliminary.