//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15503 SUBJECT: GRB 131118A: Fermi GBM detection DATE: 13/11/19 18:35:12 GMT FROM: Andrew Collazzi at NASA/MSFC/ORAU Andrew C. Collazzi (NASA/ORAU) reports on behalf of the Fermi GBM Team: "At 22:58:57.47 UT on 18 November 2013, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 131118A (trigger 406508340 / 131118.958). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 349.7, Dec = -69.4 (J2000 degrees, equivalent to J2000 23h 18.8m, -69° 24' ), with a statistical uncertainty of 1.0 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 150 degrees. Due to the high zenith angle of this burst, there may be higher than normal systematic errors on this location. This burst was also observed by Swift-BAT (ground analysis), Suzaku-WAM, and INTEGRAL/SPI-ACS. The GBM light curve shows a multi-peaked event with a duration (T90) of about 85 s (50-300 keV). The 1.024-s peak flux during this interval is 12.5 +/- 0.9 erg/s/cm^2 (10-1000 keV). The time-averaged spectrum from T0-13.8 to T0+99.8 s is equally well fit to a Comptonized model with Epeak = 370.5 +/- 10.6, alpha = -0.89 +/- 0.03 and a Band model with Epeak = 366.8 +/- 12.5, alpha = -0.89 +/- 0.03, and beta = -3.4 +/- 0.6. Both models yield a fluence (10-1000 keV) in this time interval of (9.2 +/- 0.1)E-05 erg/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15506 SUBJECT: IPN Triangulation of GRB 131118A DATE: 13/11/20 18:42:44 GMT FROM: Valentin Pal'shin at Ioffe Inst IPN Triangulation of GRB 131118A K. Hurley, and J. Goldsten, on behalf of the MESSENGER NS GRB team, S. Golenetskii, R. Aptekar, V. Pal'shin, D. Frederiks, D. Svinkin, and T. Cline on behalf of the Konus-Wind team, I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin, on behalf of the HEND-Odyssey GRB team, W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr, on behalf of the GRS-Odyssey GRB team, V. Connaughton, M. S. Briggs, C. Meegan, and V. Pelassa, on behalf of the Fermi GBM team, A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo, and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team, S. Barthelmy, J. Cummings, N. Gehrels, H. Krimm, and D. Palmer, on behalf of the Swift-BAT team, and K. Yamaoka, M. Ohno, Y. Hanabata, Y. Fukazawa, T. Takahashi, M. Tashiro, Y. Terada, T. Murakami, and K. Makishima on behalf of the Suzaku WAM team, report: The long-duration, intense GRB 131118A (Collazzi, GCN 15503) has been observed by Fermi (GBM: trigger 406508340), INTEGRAL (SPI-ACS), Swift (BAT), Suzaku (WAM), MESSENGER (GRNS), Mars Odyssey (HEND), and Konus-Wind, so far, at about 82737 s UT (22:58:57). The burst was outside the coded field of view of the BAT. We have triangulated it to a 3 sigma error box whose coordinates are: --------------------------------------------- RA(2000), deg Dec(2000), deg --------------------------------------------- Center: 349.863 (23h 19m 27s) -66.833 (-66d 49' 58") Corners: 350.415 (23h 21m 40s) -66.930 (-66d 55' 47") 349.800 (23h 19m 12s) -66.926 (-66d 55' 32") 349.313 (23h 17m 15s) -66.733 (-66d 44' 00") 349.924 (23h 19m 42s) -66.740 (-66d 44' 23") --------------------------------------------- The error box area is 162 sq. arcmin, and its maximum dimension is 29 arcmin (the minimum one is 12 arcmin). The Sun distance was 81.6 deg. The center of the GBM ground position (Collazzi, GCN 15503) is 2.6 deg from the center of the box. Some improvement in this triangulation is possible. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15507 SUBJECT: Konus-Wind observation of GRB 131118A DATE: 13/11/21 08:06:58 GMT FROM: Dmitry Frederiks at Ioffe Institute S. Golenetskii, R.Aptekar, D. Frederiks, V. Pal'shin, P. Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind team, report: The long-duration GRB 131118A (Fermi GBM detection: Collazzi, GCN 15503; IPN triangulation: Hurley at al., GCN 15506) triggered Konus-Wind at T0=82738.919 s UT (22:58:58.919). The burst light curve shows multiple partly overlapped pulses from ~T0 to ~T0+140 s. The emission is seen up to ~10 MeV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB131118_T82738/ Note: the waiting mode LCs are corrupted for almost whole duration of the burst. As observed by Konus-Wind, the burst had a fluence of (8.40 ± 0.06)x10-5 erg/cm2, and a 64-ms peak flux, measured from T0+63.296 s, of (5.1 ± 0.5)x10-5 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The time-averaged spectrum (measured from T0 to T0+139.520 s) is best fit in the 20 keV - 15 MeV range by the GRB (Band) function with the following model parameters: the low-energy photon index alpha = -0.88 ± 0.05, the high energy photon index beta = -2.83 ± 0.25, the peak energy Ep = 230 ± 11 keV, chi2 = 97.4/96 dof. The spectrum near the maximum count rate (measured from T0+57.600 s to T0+65.792 s) is best fit in the 20 keV - 15 MeV range by the GRB (Band) function with the following model parameters: the low-energy photon index alpha = -0.80 ± 0.04, the high energy photon index beta = -2.56 ± 0.07, the peak energy Ep = 286 ± 8 keV, chi2 = 110/97 dof. All the quoted values are preliminary. [GCN OPS NOTE(21nov13) The GRB name was corrected to 131118A.]