//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25633 SUBJECT: GRB 190903A: Fermi GBM Final Real-time Localization DATE: 19/09/03 17:29:59 GMT FROM: Fermi GBM Team at MSFC/Fermi-GBM The Fermi GBM team reports the detection of a likely SHORT GRB At 17:19:36 UT on 3 Sep 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190903A (trigger 589223981.255486 / 190903722). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 62.4, Dec = -64.9 (J2000 degrees, equivalent to J2000 04h 09m, -64d 54'), with a statistical uncertainty of 6.3 degrees. The angle from the Fermi LAT boresight is 86.0 degrees. The skymap can be found here: http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190903722/quicklook/glg_skymap_all_bn190903722.png The HEALPix FITS file, including the estimated localization systematic, can be found here: http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190903722/quicklook/glg_healpix_all_bn190903722.fit The GBM light curve can be found here: http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190903722/quicklook/glg_lc_medres34_bn190903722.gif //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25636 SUBJECT: GRB 190903A: Fermi GBM detection DATE: 19/09/03 23:22:28 GMT FROM: Bagrat Mailyan at UAH B. Mailyan (UAH) and C. Meegan (UAH) report on behalf of the Fermi GBM Team: "At 17:19:36.26 UT on 3 September 2019, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 190903A (trigger 589223981/190903722). The on-ground calculated location, using the GBM trigger data, is RA = 62.43 , DEC = -64.86 (J2000 degrees, equivalent to 11h 32m, -17d 46'), with an uncertainty of 6.3 degrees (radius, 1-sigma containment). The angle from the Fermi LAT boresight is 86 degrees. The GBM light curve consists of a single short spike with a duration (T90) of about 0.27s (50-300 keV). The time-averaged spectrum from T0-0.064s to T0+0.128s is adequately fit by a Band function with Epeak = 824 +/- 308 keV, alpha = -0.79 +/- 0.13, and beta = -2.15 +/- 0.36 The event fluence (10-1000 keV) in this time interval is (7.8 +/- 0.65)E-07 erg/cm^2. The 1-sec peak photon flux measured starting from T0-0.38s in the 10-1000 keV band is 3.01 +/- 0.23 ph/s/cm^2." The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog: https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html For Fermi GBM data and info, please visit the official Fermi GBM Support Page: https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25662 SUBJECT: IPN triangulation of GRB 190903A (short) DATE: 19/09/04 22:48:35 GMT FROM: Dmitry Svinkin at Ioffe Institute D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, A. Kozlova, and T. Cline on behalf of the Konus-Wind team, K. Hurley, on behalf of the IPN, A. Goldstein, M. S. Briggs, and C. Wilson-Hodge on behalf of the Fermi GBM team, and A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo, and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team, report: The short-duration GRB 190903A (Fermi-GBM detection: Fermi GBM Team, GCN Circ. 25633; Mailyan and Meegan, GCN Circ. 25636) was detected by Fermi (GBM trigger 589223981), INTEGRAL (SPI-ACS), and Konus-Wind, at about 62376 s UT (17:19:36). We have triangulated it to a preliminary, 3 sigma error box whose coordinates are: --------------------------------------------- RA(2000), deg Dec(2000), deg --------------------------------------------- Center: 63.950 (04h 15m 48s) -59.485 (-59d 29' 04") Corners: 62.459 (04h 09m 50s) -49.304 (-49d 18' 15") 66.042 (04h 24m 10s) -66.310 (-66d 18' 34") 64.926 (04h 19m 42s) -65.995 (-65d 59' 43") 61.374 (04h 05m 30s) -46.559 (-46d 33' 33") --------------------------------------------- The error box area is about 7.5 sq. deg, and its maximum dimension is 19.9 deg (the minimum one is 27.5 arcmin). The Sun distance was 100 deg. This box may be improved. The IPN localization is consistent with, but reduces the area of, the Fermi-GBM one. A triangulation map is posted at http://www.ioffe.ru/LEA/GRBs/GRB190903_T62377/IPN/ The Konus-Wind time history and spectrum will be given in a forthcoming GCN Circular.