Gamma-ray Burst 120919B

(All information courtesy of the instrument teams.)

Previous IAU Circulars

• none

• GCN Circular #13788
  K. Hurley on behalf of the Mars Odyssey and MESSENGER GRB teams,
  J. Goldsten, on behalf of the MESSENGER GRNS GRB team,
  I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin, on behalf of the HEND-Odyssey GRB team,
  S. Golenetskii, R. Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, D. Svinkin, and T. Cline on behalf of the Konus-Wind team,
  W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr, on behalf of the GRS-Odyssey GRB team,
  V. Connaughton, M. Briggs, and C. Meegan, 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 long-duration, moderately intense GRB 120919B was observed by Fermi (GBM: trigger 369710066), Konus-Wind, MESSENGER (GRNS), INTEGRAL (SPI-ACS), and Mars Odyssey (HEND) at about 4463 s UT (01:14:23).
  We have triangulated it to a preliminary, 3 sigma error box whose coordinates are:

     ---------------------------------------------
      RA(2000), deg                 Dec(2000), deg
     ---------------------------------------------
     Center:
      302.633 (20h 10m 32s) -37.490 (-37d 29' 25")
     Corners:
      302.735 (20h 10m 56s) -37.483 (-37d 28' 59")
      302.857 (20h 11m 26s) -38.235 (-38d 14' 04")
      302.530 (20h 10m 07s) -37.497 (-37d 29' 50")
      302.401 (20h 09m 36s) -36.706 (-36d 42' 21")
     ---------------------------------------------
  

  The error box area is 457 sq. arcmin, and its maximum dimension is 1.57 deg (the minimum one is 10 arcmin).
  This box can be improved.
• GCN Circular #13789
  S. Golenetskii, R.Aptekar, D. Frederiks, E. Mazets, V. Pal'shin, P. Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind team, report:
  The long-duration, moderately intense GRB 120919B (IPN detection and localization: Hurley et al., GCN 13788) triggered Konus-Wind at T0=04499.597s UT (01:14:59.401)
  The light curve shows multiple pulses in the time interval starting at ~T0-30s and ending at ~T0+100s. The emission in the main bursting episode is seen up to 8 MeV.
  The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB120919_T04499/
  As observed by Konus-Wind, the burst had a fluence of 3.1(-0.5,+0.7)x10-5 erg/cm2, and a 256-ms peak flux, measured from T0+13.056 s, of 4.3(-0.9,+1.1)x10-6 erg/cm2/s (both in the 20 keV - 10 MeV energy range).
  The time-integrated spectrum (measured from T0 to T0+98.560 s) is best fit in the 20 keV - 10 MeV range by the GRB (Band) function with the following model parameters: the low-energy photon index alpha = -0.9 (-0.4, +0.5), the high energy photon index beta = -2.3 (-2.7, +0.3), the peak energy Ep = 250(-60, +190) keV, chi2 = 86.9/83 dof.
  The spectrum of the main bursting episode (measured from T0 to T0+16.640 s) is best fit in the 20 keV - 10 MeV range by the GRB (Band) function with the following model parameters: the low-energy photon index alpha = -1.0 (-0.2, +0.2), the high energy photon index beta = -2.4 (-1.0, +0.3), the peak energy Ep = 300(-70, +85) keV, chi2 = 76.3/83 dof.
  All the quoted results are preliminary. All the quoted errors are at the 90% confidence level.
• GCN Circular #13792
  H. Levato and C. Saffe Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)
  C. Mallamaci, C. Lopez and F. Podest Observatorio Astronomico Felix Aguilar (OAFA)
  E. Gorbovskoy, V. Lipunov, V. Kornilov, D. Denisenko, A. Kuznetsov, D. Kuvshinov, A. Belinski, N. Tyurina, N. Shatskiy, P. Balanutsa, D. Zimnukhov, V.V. Chazov Lomonosov Moscow State University, Sternberg Astronomical Institute
  A. Tlatov, A.V. Parhomenko, D. Dormidontov, V. Sennik Kislovodsk Solar Station of the Pulkovo Observatory
  K. Ivanov, S. Yazev, N.M. Budnev, O. Gres, O. Chuvalaev, V.A. Poleshchuk Irkutsk State University
  V. Yurkov, Yu. Sergienko, D. Varda, E. Sinyakov Blagoveschensk Educational State University, Blagoveschensk
  V. Krushinski, I. Zalozhnich, A. Popov, A. Bourdanov Ural Federal University
  MASTER-ICATE robotic Very Wide Field Cameras (FOV=2x384 square degrees, D=72mm, f/1.2, 1 pix = 22 arcsec, http://observ.pereplet.ru) located in Argentina (Observatorio Astronomico Felix Aguilar, http://93.180.27.230:8080/) were pointed to the GRB120919B by FERMI 369710066 trigger 30 s after notice time and 55 s after GRB time at 2012-09-19 01:15:18 UT. We cover full IPN-triangulations error-box (K. Hurley et. al. GCN13788) We haven`t found optical transient within IPN-triangulations error-box our first (5 s exposure) set and on coadd image with complete exposure of 45 seconds durnig gamma-burst activity (Golenetskii et al., GCN 13789).
  The 5-sigma upper limit on single image has been about 11.7 mag and 12.5 mag on coadded image.
  Also, we are marginaly see ~2 sigma OT at position Ra 20:10:26.40 Dec +37:31:48.00 with magnitude 12.5+-0.5m .
  The coverage map and OT image available here http://master.sai.msu.ru/static/GRB/GRB120919B_2x2deg.png
  Our cameras are continuously imaging the sky with 5 sec exposures.
  This message can be cited.