Gamma-ray Burst 001120

(All information courtesy of the instrument teams.)

Previous IAU Circulars

• none

• GCN notice #888
  K. Hurley, on behalf of the Ulysses GRB team, T. Cline, on behalf of the Konus-Wind and NEAR GRB teams, and E. Mazets, and S. Golenetskii, on behalf of the KONUS-WIND GRB team, report:
  Ulysses, NEAR, and KONUS-WIND observed this GRB at 49531 seconds. As observed by Ulysses, it had a duration of approximately 20. seconds, a 25-100 keV fluence of approximately 1.0E-05 erg/cm2, and a peak flux of approximately 9.4E-07 erg/cm2 s over 1.00 second. We have triangulated it to a preliminary, 3 sigma error box with approximate area 66. sq. arcmin. whose coordinates are:
  

   ERROR BOX CENTER:  22 h 18 m 27.70 s      1 o  5 '  38.89 " 
   ERROR BOX CORNER 1: 22 h 18 m 33.37 s      1 o  3 '  20.50 " 
   ERROR BOX CORNER 2: 22 h 17 m 27.99 s      1 o  6 '  51.96 " 
   ERROR BOX CORNER 3: 22 h 19 m 26.75 s      1 o  4 '  29.18 " 
   ERROR BOX CORNER 4: 22 h 18 m 22.02 s      1 o  7 '  57.30 " 
  

  This error box may be improved.
• GCN notice #890
  D. Kaiser (Crescent Moon Observatory) D. Durig (Cordell-Lorenz Observatory) A. Henden (USRA/USNO) report:
  We have observed the error box of GRB001120 as part of the monitoring effort by the AAVSO GRB network. This error box is quite long in RA (30arcmin), and so the images only cover the central portion of that box, missing the extreme east and west corners. There are a few galaxies visible, so the visual extinction is not large in this high galactic latitude field (bII=-43).
  The limiting magnitude in the table below is based on the r-magnitude of a set of USNO-A2.0 stars in the field. Unfiltered observations are listed with a "C" in the filter column. The seeing measures are an upper limit due to undersampling in both datasets.

  --------------------------------------------------------------------------
     Date (UT)   Telescope  filter  RA width   exposure    seeing   limiting
     (Midpt)                        (arcmin)    (sec)     (arcsec)    mag.
  --------------------------------------------------------------------------
    Nov. 22.036    0.35-m      R     17.9     12 * 300      4.4     19.8
    Nov. 22.051    0.30-m      C     26.9     10 * 600      3.8     20.8
  --------------------------------------------------------------------------
  

  All objects on the Nov22.036 dataset are also visible in the scans of the POSS-2 red plate from the NOFS PMM pixel server. The Nov22.051 dataset goes slightly deeper than the POSS-2 plate, and a second CCD epoch will be necessary to exclude the fainter objects.
• GCN notice #892
  P. A. Price, J. Meltzer, B. Stalder, S. G. Djorgovski, and T. J. Galama, on behalf of a large collaboration, report:
  We have observed the error box of GRB 001120 with 3x900s pointings in gunn-r on the Palomar 60-inch telescope at 2000 Nov 22.12 and Nov 24.12. Our images cover the entire error box, with approximate limiting magnitude R ~ 22.5 (based on the USNO catalogue) at both epochs. We do not find any optical transient candidate within the error box on comparison with the DPOSS, or from subtraction of the two epochs.
• GCN notice #893
  P. A. Price, J. Meltzer, B. Stalder, S. G. Djorgovski, and T. J. Galama, on behalf of a large collaboration, report:
  In addition to the gunn-r observations reported in GCN #892, we also observed the error box of GRB 001120 in gunn-i with 6 x 500s pointings on 2000 Nov 22.18 and Nov 24.18. Our images cover the entire error box. We do not find any optical transient candidate from these observations, either from comparison with the DPOSS, or from subtraction of the two epochs. The magnitude limit is uncertain, but estimated to be i ~ 22.5 mag at each epoch. This argues against the hypothesis that an optical afterglow was undetected due to either a high redshift (z > 5) or a modest obscuration by dust.