TITLE: GCN CIRCULAR NUMBER: 9647 SUBJECT: Konus-Wind and Konus-RF observations of GRB 090709A DATE: 09/07/10 10:43:10 GMT FROM: Dmitry Frederiks at Ioffe Institute S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, 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 090709A (Morris et al., GCN 9625) triggered Konus-Wind at T0=27514.965 s UT (07:38:34.965), and Konus-RF instrument onboard CORONAS-PHOTON s/c at T0(KRF)=27513.934 s UT (07:38:33.934). The burst light curve shows a multi-peaked structure with a duration of ~100 s. We confirm presence of quasi-period in the light curve (Markwardt et al., GCN 9645). The corresponding peaks in the FFT power spectrum of 128 ms light curve are clearly seen around P=8.28s (0.1208 Hz) and P=16.56s (0.0604 Hz). The Konus-Wind light curves of this GRB are vailable at http://www.ioffe.ru/LEA/GRBs/GRB090709_T27514/ The normalized power spectrum of the detrended Konus-Wind light curve (128 ms, in 20-1150 keV range) is available at http://www.ioffe.ru/LEA/GRBs/GRB090709_T27514/GRB090709_T27514_KW_power.png As observed by Konus-Wind the burst had a fluence of (9.1 ± 0.07)x10-5 erg/cm2, and a 256-ms peak flux measured from T0+23.308 s of (3.9 ± 0.6)x10-6 erg/cm2/s (both in the 20 keV - 3 MeV energy range). The time-integrated spectrum of the burst (from T0 to T0+102.912 s) is well fitted (in the 20 keV - 3 MeV range) by GRB (Band) model for which: the low-energy photon index alpha = -0.85 ± 0.08, the high-energy photon index beta = -2.7(-0.3, +0.2), the peak energy Ep = 298 ± 27 keV (chi2 = 71/67 dof). The spectrum at the maximum count rate, measured from T0+16.640 to T0+24.320 s, is well fitted (in the 20 keV - 3 MeV range) by GRB (Band) model for which: the low-energy photon index alpha = -0.86 (-0.07, +0.10), the high-energy photon index beta = -2.6(-2.6, +0.53), the peak energy Ep = 416(-100, +95) keV (chi2 = 63/67 dof). All the quoted values are preliminary. The quoted errors are at the 90% confidence level.