TITLE: GCN CIRCULAR NUMBER: 44617 SUBJECT: Konus-Wind detection of GRB 260512A DATE: 26/05/15 10:45:03 GMT FROM: Anna Ridnaia at Ioffe Institute <ridnaia@mail.ioffe.ru> A. Ridnaia, D. Frederiks, A. Lysenko, D. Svinkin, A. Tsvetkova, M. Ulanov, and T. Cline, on behalf of the Konus-Wind team, report: The long-duration GRB 260512A (Fermi-GBM detection: The Fermi GBM team, GCN 44587; NuSTAR-ACS detection: Waratkar et al., GCN 44591; AstroSat-CZTI detection: Tembhurnikar et al., GCN 44608; IPN triangulation: Kozyrev et al., GCN 44611) triggered Konus-Wind at T0=61005.883 s UT (16:56:45.883). The burst light curve shows a multipeaked structure which starts at ~T0-0.7 s and has a total duration of ~23 s. The emission is seen up to ~2 MeV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB260512_T61005/ As observed by Konus-Wind, the burst had the total fluence of 2.45(-0.24,+0.20)x10^-5 erg/cm2, and the 64-ms peak flux, measured from T0+4.464 s, of 6.32(-0.82,+0.83)x10^-6 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The time-averaged spectrum of the burst (measured from T0 to T0+24.832 s) is best fit in the 20 keV - 10 MeV range by the GRB (Band) model with the following parameters: the low-energy photon index alpha = -0.99(-0.09,+0.09), the high energy photon index beta = -2.60(-0.46,+0.17), the peak energy Ep = 202(-16,+22) keV (chi2 = 117/98 dof). The spectrum near the maximum count rate (measured from T0+0.256 to T0+8.448 s) is best fit in the 20 keV - 10 MeV range by the GRB (Band) model with the following parameters: the low-energy photon index alpha = -0.82(-0.08,+0.08), the high energy photon index beta = -2.53(-0.13,+0.10), the peak energy Ep = 193(-11,+13) keV (chi2 = 93/79 dof). All the quoted errors are at the 68% confidence level. All the quoted values are preliminary. View this GCN Circular online at https://gcn.nasa.gov/circulars/44617. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...