TITLE: GCN CIRCULAR NUMBER: 8928 SUBJECT: Konus-RF catches first GRB and SGR bursts DATE: 09/03/04 15:01:46 GMT FROM: Valentin Pal'shin at Ioffe Inst S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, V. Il'inskii, P. Oleynik, M. Ulanov, D. Svinkin, on behalf of the Konus-RF and Konus-Wind teams, report: At 07:25:57 UT on February 27, 2009 the KONUS-RF gamma-ray spectrometer detected its first gamma-ray burst, GRB 090227A (Fermi/GBM trigger 257412359 / 090227310: Bissaldi GCN 8917). That day at 13:43:36 UT the instrument detected a bright short soft burst from the AXP/SGR 1E1547.0-5408. Both bursts also triggered Konus-Wind. The Konus-RF gamma-ray spectrometer is an instrument of the CORONAS-PHOTON solar space observatory that was launched on January 30, 2009 into a low-Earth low-eccentricity, high-inclination orbit (altitude 547-592 km, inclination 82.5 deg). CORONAS-PHOTON is a 3-axis stabilized, Sun-pointing spacecraft. Konus-RF has been successfully operating since February 19. The Konus-RF experiment is aimed at studying of temporal and spectral characteristics of solar flares, gamma-ray bursts, and SGR bursts in a wide energy range from 10 keV to 10 MeV. It consists of two identical omnidirectional detectors one of which points toward the Sun thereby observing the solar hemisphere, and the other observes the antisolar hemisphere. Thus, the instrument provides continuous monitoring of the unocculted sky. However, the usable exposure time is severely limited by passage through the radiation belts at high latitudes and the South Atlantic Anomaly. Each detector employs NaI(Tl) crystal, 127 mm in diameter and 76.2 mm in height, supplied with a beryllium entrance window. The Konus-RF instrument is an advanced modification of the Russian-American Konus-Wind spectrometer. More details can be found at http://www.astro.mephi.ru/coronos-photon_conusrf_e.htm The Konus-RF and Konus-Wind light curves of the SGR burst 090227 are available at http://www.ioffe.ru/LEA/SGRs/090227_T49414/