//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9692 SUBJECT: GRB 090717: Fermi GBM detection DATE: 09/07/20 14:54:27 GMT FROM: Sylvain Guiriec at UAH E. Kara (NASA MSFC/Barnard College), S. Guiriec (UAH) and V. Chaplin (UAH) report on behalf of the Fermi GBM Team: "At 00:49:32.11 UT on 17 July 2009, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 090717 (trigger 269484574 / 090717034). The on-ground calculated location, using the GBM trigger data, is RA = 86.8, DEC = -64.2 (J2000 degrees, equivalent to 05 h 47 m, -64 d 12 '), with an uncertainty of 1.0 degree (radius, 1-sigma containment, statistical only; there is additionally a systematic error which is currently estimated to be 2 to 3 degrees). The angle from the Fermi LAT boresight is 70 degrees. This burst was also independently detected by INTEGRAL SPI-ACS. The GBM light curve shows two peaks with a duration (T90) of about 70 s (8-1000 keV). The time-averaged spectrum of the two peaks fit together from T0+2.8 s to T0+12.0 s and T0+44.8 to T0+52.0 is adequately fit by a Band function with Epeak = 120 +/- 5 keV, alpha = -0.88 +/- 0.04, and beta = -2.33 +/- 0.06 (chi squared 967 for 845 d.o.f.). The event fluence (8-1000 keV) in this time interval is (4.5 +/- 0.2)E-07 erg/cm^2. The 1-sec peak photon flux measured starting from T0+2.8 s in the 8-1000 keV band is 7.8 +/- 0.7 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9693 SUBJECT: GRB 090717B: Fermi GBM detection DATE: 09/07/20 14:56:58 GMT FROM: Arne Rau at MPE Arne Rau (MPE) reports on behalf of the Fermi GBM Team: "At 02:40:31.79 UT on 17 July 2009, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 090717B (trigger 269491233 / 090717111). The on-ground calculated location, using the GBM trigger data, is RA = 247.0, DEC = 23.0 (J2000 degrees, equivalent to 16 h 28m m, 23 d 00 '), with an uncertainty of 3.9 degrees (radius, 1-sigma containment, statistical only; there is additionally a systematic error which is currently estimated to be 2 to 3 degrees). The angle from the Fermi LAT boresight is 35 degrees. This burst was also independently detected (although not triggered) by INTEGRAL SPI-ACS. The GBM light curve consists of a single peak with a duration (T90) of about 0.9 s (8-1000 keV). The time-averaged spectrum from T0-0.256s to T0+0.128 s is adequately fit by a simple power law function with index -1.02 +/- 0.04 (chi squared 604 for 732 d.o.f.). The event fluence (8-1000 keV) in this time interval is (4.83 +/- 0.03)E-07 erg/cm^2. The 0.384-sec peak photon flux measured starting from T0-0.256 s in the 8-1000 keV band is 3.91 +/- 0.42 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9738 SUBJECT: GRB 090717A: Suzaku WAM observation of the prompt emission DATE: 09/07/31 12:42:00 GMT FROM: Kazutaka Yamaoka at Aoyama Gakuin U N. Vasquez (Tokyo Tech.), K. Yamaoka, S. Sugita (Aoyama Gakuin U.), K. Noda, E. Sonoda, M. Yamauchi, N. Ohmori, H. Hayashi, K. Kono, A. Daikyuji, Y. Nishioka (Univ. of Miyazaki), Y. Hanabata, T. Uehara, T. Takahashi, Y. Fukazawa (Hiroshima U.), M. Ohno, M. Suzuki, M. Kokubun, T. Takahashi (ISAS/JAXA), W. Iwakiri, M. Tashiro, Y. Terada, A. Endo, K. Onda, T. Sugasahara (Saitama U.), Y. Urata (NCU), T. Enoto, K. Nakazawa, K. Makishima (Univ. of Tokyo), Y. E. Nakagawa, T. Tamagawa (RIKEN), S. Hong (Nihon U.), on behalf of the Suzaku WAM team, report: The long GRB 090717A (Fermi-GBM trigger #269484574; Kara et al., GCN 9692), triggered the Suzaku Wide-band All-sky Monitor (WAM) which covers an energy range of 50 keV - 5 MeV at 00:49:32.019 UT. The light curve shows a double pulse structure with a duration (T90) of 56 seconds. The fluence in 100 - 1000 keV was 1.10(-0.15, +0.12) x10^-5 erg/cm^2. The 1-s peak flux measured from T0+6 s was 3.14(-0.53, +0.36) photons/cm^2/s in the same energy range. Preliminary result shows that the time-averaged spectrum from T0 to T0+60 s is well fitted by a single power-law model with a photon index of 2.13(-0.22, +0.33) (chi^2/d.o.f. = 15.1/17). All the quoted errors are at statistical 90% confidence level, in which the systematic uncertainties are not included. The light curves for this burst are now available at: http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html