Gamma-ray Burst 141205A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

• none

• GCN Circular #17137
  J. R. Cummings reports on behalf of the Swift science team:
  At 08:05:17, BAT triggered on GRB 141205A (trigger 620534). No source was found onboard. A significant source was found in ground analysis at RA, Dec 92.881, +37.862, which is:

  RA (J2000)   06h 11m 31.5s
  Dec (J2000)  37d 51' 43"
  

  with an estimated position uncertainty of 3 arcmin radius.
  This was the same event as Fermi GBM trigger 439459520. The BAT position is 14.0 degrees from the GBM final position (4.4 degree radius 1 sigma error).
  The burst was about 1 second long.
  A Swift TOO has been requested.
• GCN Circular #17140
  C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings, N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (LANL), A. Vargas (PSU) (i.e. the Swift-BAT team):
  We report further analysis of GRB 141205A (Cummings, GCN 17137). The best BAT position is RA, Dec 92.859, +37.876, which is:

  RA (J2000)    06 11 26.1s
  Dec (J2000)  +37d 52' 32.2"
  

  with an estimated position uncertainty of 2 arcmin radius. The source was 41% coded in BAT.
  The unweighted lightcurve shows multiple weak peaks. T90 was 1.1 +- 0.2 seconds.
  The total spectrum in BAT is best fit by a simple power-law function with a photon index of 0.985 +- 0.002. The fluence in 1.4 seconds was (1.2 +- 0.3) x 10^-7 ergs/cm^2. Errors are 90% confidence.
  Because this burst was found in ground analysis, the normal automated burst analysis products are not available.
• GCN Circular #17141
  R. L. C. Starling and K. L. Page (U. Leicester) report
  The Swift ground-analysis-detected short/hard GRB 141205A (Cummings et al. GCN 17137, 17140) was observed with XRT on 2014-12-05 starting at 14:44 UT, 6.65 hours after the burst, and ending at 2014-12-05 at 17:55 UT.
  The Photon Counting mode data comprise 4.97 ks of exposure, in which no new source is detected to a 3-sigma limit in the 0.3-10 keV band of 2.8e-3 count/s.
  This circular is an official product of the Swift XRT team.
• GCN Circular #17142
  D. Xu (DARK/NBI), H.-B. Niu, A. Esamdin, L. Ma (XAO) report:
  We observed the field of GRB 141205A (Cummings, GCN 17137), using the 1m telescope located at Nanshan, Xinjiang, China. Observations were performed between 17:26:18 UT and 21:26:52 UT on 2014-12-05, and a series of R-band 120s/200s exposures were obtained. No credible uncatalogued optical transient was found within the BAT error circle (Markwardt et al., GCN 17140), down to a limiting magnitude of R~20.4 mag.
• GCN Circular #17143
  O.J. Roberts (UCD) reports on behalf of the Fermi GBM Team:
  "At 08:05:17.49 UT on the 5th of December 2014, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 141205A (trigger 439459520 / 141205337 ), which was also detected by Swift (Cummings et al. 2014, GCN 17137). The GBM on-ground location, using the Fermi GBM trigger data, is consistent with the Swift location.
  The angle from the Fermi LAT boresight is about 123 degrees.
  The GBM light curve consists of a single peak with a duration (T90) of about 1.5 s (50-300 keV). The time-averaged spectrum from T0-0.26 s to T0+1.3 s is adequately fit by a power law function with an exponential high-energy cutoff. The power law index is -0.23 +/- 0.39 and the cutoff energy, parameterized as Epeak, is 525 +/- 164 keV.
  The event fluence (10-1000 keV) in this time interval is (1.1 +/- 0.2)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0-0.1 s in the 10-1000 keV band is 2.5 +/- 0.3 ph/s/cm^2.
  The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
• GCN Circular #17144
  M. M. Chester (PSU), F. E. Marshall (NASA/GSFC), and R. L. C. Starling (U.Leicester) report on behalf of the Swift/UVOT team:
  The Swift/UVOT began settled observations of the field of GRB 141205A 23934 s after the BAT trigger (Cummings, GCN Circ. 17137). No new sources are detected within the refined BAT error circle (Markwardt et al. GCN Circ. 17140). Using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373), we find the following 3-sigma upper limits at the center of the BAT error circle:

  Filter         T_start(s)   T_stop(s)      Exp(s)         Mag
  
  white            23975        28936          837         >21.7
  v                24016        29758          826         >20.1
  u                23934        28114          837         >20.7
  

  The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.24 in the direction of the burst (Schlegel et al. 1998).