TITLE: GCN CIRCULAR NUMBER: 9704 SUBJECT: Konus-Wind and Konus-RF observations of GRB 090719 DATE: 09/07/24 12:11:25 GMT FROM: Dmitry Frederiks at Ioffe Institute S. Golenetskii, R.Aptekar, D. Frederiks, E. Mazets, V. Pal'shin, P. Oleynik, M. Ulanov, and D. Svinkin on behalf of the Konus-Wind and Konus-RF teams, and T. Cline on behalf of the Konus-Wind team, report: The long GRB 090719 (Fermi/GBM trigger 269659888/090719063; A.J. van der Horst, GCN 9691) triggered Konus-Wind at T0=05489.199 s UT (01:31:29.199), and Konus-RF instrument onboard CORONAS-PHOTON s/c at T0=05487.876 s UT (01:31:27.876), The burst light curve shows a smooth structure with a duration of ~20 s. The Konus-RF and Konus-Wind light curves of this GRB are available at http://www.ioffe.ru/LEA/GRBs/GRB090719_T05489/ =========================================================== As observed by Konus-Wind the burst had a fluence of (4.6 ± 0.1)x10-5 erg/cm2, and a 64-ms peak flux, measured from T0+4.992 s, of 9.4(-0.5, +0.6)x10-6 erg/cm2/s (both in the 20 keV - 2 MeV energy range). The time-integrated spectrum of the burst (from T0 to T0+16.128 s) is well fit (in the 20 keV - 2 MeV range) by GRB (Band) model for which: the low-energy photon index alpha = -0.76 ± 0.05, the high energy photon index beta = -4.7( < -3.3), the peak energy Ep = 260(-11, +10) keV (chi2 = 50/48 dof). The spectrum at the maximum count rate (from T0+4.096 to T0+5.120 s) is well fit (in the 20 keV - 2 MeV range) by GRB (Band) model for which: the low-energy photon index alpha = -0.44(-0.56,+0.31), the high energy photon index beta = -3.7( < -2.8), the peak energy Ep = 328(-31, +32) keV (chi2 = 50/48 dof). =========================================================== As observed by Konus-RF the burst had a fluence of 5.2(-0.15, +0.15)x10-5 erg/cm2, and a 64-ms peak flux, measured from T0+3.368s, of 1.1(-0.1, +0.1)x10-5 erg/cm2/s (both in the 20 keV - 2 MeV energy range). The time-integrated spectrum of the burst (from T0-2.0 to T0+20.0 s) is well fit (in the 20 keV - 2 MeV range) by GRB (Band) model for which: the low-energy photon index alpha = -0.85 ± 0.5, the high energy photon index beta = -3.7( < -3.0), the peak energy Ep = 286(-15, +15) keV (chi2 = 141/130 dof). The spectrum at the maximum count rate (from T0+3.0 to T0+3.5 s) is well fit (in the 20 keV - 2 MeV range) by GRB (Band) model for which: the low-energy photon index alpha = -0.26(-0.19,+0.28), the high energy photon index beta = -2.9( < -2.3), the peak energy Ep = 327(-60, +60) keV (chi2 = 73/70 dof). =========================================================== Due to uncertainties in the burst incident angles the quoted values are preliminary. All the quoted errors are at the 90% confidence level. --