//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 10223 SUBJECT: GRB 091126: Fermi GBM detection DATE: 09/12/01 10:18:21 GMT FROM: Sheila McBreen at MPE D. Tierney (UCD) and S. McBreen (UCD/MPE) report on behalf of the Fermi GBM Team: "At 07:59:24.76 UT on 26 November 2009, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 091126 (trigger 280915166 / 091126333). The on-ground calculated location, using the GBM trigger data, is RA = 83.3, DEC = -19.3 (J2000 degrees, equivalent to 05 h 33 m, -19 d 18 '), with an uncertainty of 5.4 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 93 degrees. This burst was also independently detected by INTEGRAL SPI-ACS. The GBM light curve consists of one pulse with a duration of about 0.3 s (8-1000 keV). The time-averaged spectrum from T0-0.256 s to T0+0.256 s is adequately a power law function with an exponential high energy cutoff. The power law index is -0.60 (+0.24/-0.21) and the cutoff energy, parameterized as Epeak, is 458 (+215/-107) keV (CSTAT 478 for 476 d.o.f.). The event fluence (8-1000 keV) in this time interval is (5.9 +/- 0.5)E-7 erg/cm^2. The 0.128 sec peak photon flux measured starting from T0+0 s in the 8-1000 keV band is 8.3 +/- 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: 10237 SUBJECT: GRB 091126A: Suzaku WAM observation of the prompt emission DATE: 09/12/03 06:12:46 GMT FROM: Hidenori Hayasi at Miyazaki U H. Hayashi, Y.Nishioka, N. Ohmori, A. Daikyuji,E. Sonoda, K. Kono, K. Noda, M. Yamauchi (Univ. of Miyazaki), T. Sugasahara, M. Tashiro, Y. Terada, A. Endo, K. Onda, W. Iwakiri (Saitama U.), S. Sugita(Nagoya U.), K. Yamaoka (Aoyama Gakuin U.), M. Ohno, M. Suzuki, M. Kokubun, T. Takahashi (ISAS/JAXA), Y. E. Nakagawa, T. Tamagawa (RIKEN), N. Vasquez (Tokyo Tech.), Y. Urata, H.M Lin (NCU), Y. Hanabata, T. Uehara, T. Takahashi, Y. Fukazawa (Hiroshima U.), T. Enoto, K. Nakazawa, K. Makishima (Univ. of Tokyo), S. Hong (Nihon U.), on behalf of the Suzaku WAM team, report The short GRB 091126A (Fermi/GBM trigger #280915166 ; Tierney et al., GCN 10223) triggered the Suzaku Wide-band All-sky Monitor (WAM) which covers an energy range of 50 keV - 5 MeV at 2009-11-26 07:59:24.67 UT (=T0) The observed light curve shows a single peak starting at T0 , ending at T0+0.5 s with a duration (T90) of about 0.3 seconds. The fluence in 100 - 1000 keV was 5.76 (-1.72,+1.47) x10^-7 erg/cm^2. The 1-s peak flux measured from T0 was 1.57 (-0.84,+0.39) photons/cm^2/s in the same energy range. Preliminary result shows that the time-averaged spectrum from T0 to T0+0.5 s is well fitted by a single power-law with a photon index of 2.27 (-0.43,+0.55) (chi^2/d.o.f. = 20/16). The power-law with exponential cutoff model also gives a good fit with the Epeak of 303(-99,+151) keV, assuming the power-law index of -0.6 as was reported by Tierney et al. (GCN 10223). 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 available at: http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html