Gamma-ray Burst 131209A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

• none

• GCN NOTICE
  

  TITLE:           GCN/FERMI NOTICE
  NOTICE_DATE:     Mon 09 Dec 13 13:08:21 UT
  NOTICE_TYPE:     Fermi-GBM Flight Position
  RECORD_NUM:      44
  TRIGGER_NUM:     408287279
  GRB_RA:          138.050d {+09h 12m 12s} (J2000),
                   138.194d {+09h 12m 47s} (current),
                   137.534d {+09h 10m 08s} (1950)
  GRB_DEC:         -33.850d {-33d 51' 00"} (J2000),
                   -33.908d {-33d 54' 27"} (current),
                   -33.644d {-33d 38' 37"} (1950)
  GRB_ERROR:       20.72 [deg radius, statistical plus systematic]
  GRB_INTEN:       86 [cnts/sec]
  DATA_SIGNIF:     5.90 [sigma]
  INTEG_TIME:      2.048 [sec]
  GRB_DATE:        16635 TJD;   343 DOY;   13/12/09
  GRB_TIME:        47276.97 SOD {13:07:56.97} UT
  GRB_PHI:         225.00 [deg]
  GRB_THETA:        20.00 [deg]
  DATA_TIME_SCALE: 2.0480 [sec]
  HARD_RATIO:      0.72
  LOC_ALGORITHM:   3 (version number of)
  MOST_LIKELY:      97%  GRB
  2nd_MOST_LIKELY:   2%  Generic Transient
  DETECTORS:       0,0,0, 0,0,0, 1,1,0, 0,0,0, 0,0,
  SUN_POSTN:       256.55d {+17h 06m 12s}  -22.86d {-22d 51' 38"}
  SUN_DIST:         98.42 [deg]   Sun_angle= 7.9 [hr] (West of Sun)
  MOON_POSTN:      345.99d {+23h 03m 58s}   -1.56d {-01d 33' 27"}
  MOON_DIST:       135.95 [deg]
  MOON_ILLUM:      49 [%]
  GAL_COORDS:      259.38,  9.90 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:      155.02,-47.05 [deg] ecliptic lon,lat of the burst (or transient)
  COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
  COMMENTS:        This trigger occurred at longitude,latitude = 230.22,19.67 [deg].  
  

• GCN NOTICE
  

  TITLE:           GCN/FERMI NOTICE
  NOTICE_DATE:     Mon 09 Dec 13 13:08:30 UT
  NOTICE_TYPE:     Fermi-GBM Flight Position
  RECORD_NUM:      57
  TRIGGER_NUM:     408287279
  GRB_RA:          134.417d {+08h 57m 40s} (J2000),
                   134.548d {+08h 58m 11s} (current),
                   133.947d {+08h 55m 47s} (1950)
  GRB_DEC:         -40.683d {-40d 40' 59"} (J2000),
                   -40.738d {-40d 44' 15"} (current),
                   -40.489d {-40d 29' 20"} (1950)
  GRB_ERROR:       6.08 [deg radius, statistical plus systematic]
  GRB_INTEN:       302 [cnts/sec]
  DATA_SIGNIF:     32.40 [sigma]
  INTEG_TIME:      4.096 [sec]
  GRB_DATE:        16635 TJD;   343 DOY;   13/12/09
  GRB_TIME:        47276.97 SOD {13:07:56.97} UT
  GRB_PHI:         240.00 [deg]
  GRB_THETA:        25.00 [deg]
  DATA_TIME_SCALE: 4.0960 [sec]
  HARD_RATIO:      0.48
  LOC_ALGORITHM:   3 (version number of)
  MOST_LIKELY:      95%  GRB
  2nd_MOST_LIKELY:   4%  Generic Transient
  DETECTORS:       0,0,0, 0,0,0, 1,1,0, 0,0,0, 0,0,
  SUN_POSTN:       256.55d {+17h 06m 12s}  -22.86d {-22d 51' 38"}
  SUN_DIST:         96.69 [deg]   Sun_angle= 8.1 [hr] (West of Sun)
  MOON_POSTN:      345.99d {+23h 03m 58s}   -1.56d {-01d 33' 25"}
  MOON_DIST:       128.94 [deg]
  MOON_ILLUM:      49 [%]
  GAL_COORDS:      262.60,  3.21 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:      155.88,-54.44 [deg] ecliptic lon,lat of the burst (or transient)
  COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
  COMMENTS:        This trigger occurred at longitude,latitude = 230.22,19.67 [deg].  
  

• GCN NOTICE
  

  TITLE:           GCN/FERMI NOTICE
  NOTICE_DATE:     Mon 09 Dec 13 13:08:37 UT
  NOTICE_TYPE:     Fermi-GBM Ground Position
  RECORD_NUM:      56
  TRIGGER_NUM:     408287279
  GRB_RA:          130.990d {+08h 43m 58s} (J2000),
                   131.120d {+08h 44m 29s} (current),
                   130.524d {+08h 42m 06s} (1950)
  GRB_DEC:         -39.700d {-39d 42' 00"} (J2000),
                   -39.751d {-39d 45' 02"} (current),
                   -39.518d {-39d 31' 05"} (1950)
  GRB_ERROR:       4.81 [deg radius, statistical only]
  DATA_SIGNIF:     13.30 [sigma]
  DATA_INTERVAL:   4.096 [sec]
  GRB_DATE:        16635 TJD;   343 DOY;   13/12/09
  GRB_TIME:        47276.97 SOD {13:07:56.97} UT
  GRB_PHI:         236.00 [deg]
  GRB_THETA:        27.00 [deg]
  E_RANGE:         44.032 - 279.965 [keV]
  LOC_ALGORITHM:   4143 (Gnd S/W Version number)
  SUN_POSTN:       256.55d {+17h 06m 12s}  -22.86d {-22d 51' 38"}
  SUN_DIST:         99.34 [deg]   Sun_angle= 8.4 [hr] (West of Sun)
  MOON_POSTN:      345.99d {+23h 03m 58s}   -1.56d {-01d 33' 23"}
  MOON_DIST:       127.82 [deg]
  MOON_ILLUM:      49 [%]
  GAL_COORDS:      260.18,  1.81 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:      151.09,-54.79 [deg] ecliptic lon,lat of the burst (or transient)
  COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
  COMMENTS:        In the LAT Field-of-view.  
  COMMENTS:        This Notice was ground-generated -- not flight-generated.  
  

• GCN NOTICE
  

  TITLE:           GCN/FERMI NOTICE
  NOTICE_DATE:     Mon 09 Dec 13 13:08:41 UT
  NOTICE_TYPE:     Fermi-GBM Ground Position
  RECORD_NUM:      68
  TRIGGER_NUM:     408287279
  GRB_RA:          136.710d {+09h 06m 50s} (J2000),
                   136.849d {+09h 07m 24s} (current),
                   136.210d {+09h 04m 50s} (1950)
  GRB_DEC:         -36.340d {-36d 20' 23"} (J2000),
                   -36.397d {-36d 23' 47"} (current),
                   -36.138d {-36d 08' 16"} (1950)
  GRB_ERROR:       2.08 [deg radius, statistical only]
  DATA_SIGNIF:     36.10 [sigma]
  DATA_INTERVAL:   4.096 [sec]
  GRB_DATE:        16635 TJD;   343 DOY;   13/12/09
  GRB_TIME:        47276.97 SOD {13:07:56.97} UT
  GRB_PHI:         231.00 [deg]
  GRB_THETA:        22.00 [deg]
  E_RANGE:         44.032 - 279.965 [keV]
  LOC_ALGORITHM:   4143 (Gnd S/W Version number)
  SUN_POSTN:       256.55d {+17h 06m 12s}  -22.86d {-22d 51' 38"}
  SUN_DIST:         97.87 [deg]   Sun_angle= 8.0 [hr] (West of Sun)
  MOON_POSTN:      345.99d {+23h 03m 58s}   -1.56d {-01d 33' 23"}
  MOON_DIST:       133.37 [deg]
  MOON_ILLUM:      49 [%]
  GAL_COORDS:      260.51,  7.42 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:      155.19,-49.76 [deg] ecliptic lon,lat of the burst (or transient)
  COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
  COMMENTS:        In the LAT Field-of-view.  
  COMMENTS:        This Notice was ground-generated -- not flight-generated.  
  

• GCN NOTICE
  

  TITLE:           GCN/FERMI NOTICE
  NOTICE_DATE:     Mon 09 Dec 13 13:08:39 UT
  NOTICE_TYPE:     Fermi-GBM Flight Position
  RECORD_NUM:      69
  TRIGGER_NUM:     408287279
  GRB_RA:          134.683d {+08h 58m 44s} (J2000),
                   134.814d {+08h 59m 15s} (current),
                   134.213d {+08h 56m 51s} (1950)
  GRB_DEC:         -40.667d {-40d 40' 00"} (J2000),
                   -40.721d {-40d 43' 16"} (current),
                   -40.472d {-40d 28' 17"} (1950)
  GRB_ERROR:       4.83 [deg radius, statistical plus systematic]
  GRB_INTEN:       612 [cnts/sec]
  DATA_SIGNIF:     47.50 [sigma]
  INTEG_TIME:      2.048 [sec]
  GRB_DATE:        16635 TJD;   343 DOY;   13/12/09
  GRB_TIME:        47276.97 SOD {13:07:56.97} UT
  GRB_PHI:         240.00 [deg]
  GRB_THETA:        25.00 [deg]
  DATA_TIME_SCALE: 2.0480 [sec]
  HARD_RATIO:      0.37
  LOC_ALGORITHM:   3 (version number of)
  MOST_LIKELY:      96%  GRB
  2nd_MOST_LIKELY:   3%  Generic Transient
  DETECTORS:       0,0,0, 0,0,0, 1,1,0, 0,0,0, 0,0,
  SUN_POSTN:       256.55d {+17h 06m 12s}  -22.86d {-22d 51' 38"}
  SUN_DIST:         96.54 [deg]   Sun_angle= 8.1 [hr] (West of Sun)
  MOON_POSTN:      345.99d {+23h 03m 58s}   -1.56d {-01d 33' 23"}
  MOON_DIST:       129.08 [deg]
  MOON_ILLUM:      49 [%]
  GAL_COORDS:      262.72,  3.37 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:      156.17,-54.33 [deg] ecliptic lon,lat of the burst (or transient)
  COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
  COMMENTS:        This trigger occurred at longitude,latitude = 230.22,19.67 [deg].  
  

• GCN Circular #15587
  G.Vianello (Stanford), N.Omodei (Stanford), report on behalf of the Fermi-LAT team:
  At 13:07:56.97on December 9, 2013, Fermi LAT detected a faint high energy signal from GRB 131209A, which was also detected by Fermi-GBM (trigger 408287279/131209547).
  The data from the Fermi LAT show a significant increase in the event rate within 10 degree of the GBM location after the GBM trigger that is spatially and temporally correlated with the GBM emission. Although the detection is slightly above the 5 sigma level, there are only 4 photons likely associated with this GRB in the first 200 s after the trigger. The localization has therefore a large statistical error. The best LAT on-ground location is found to be RA, DEC 136.5, -33.2 (J2000) with an error radius of 0.9 deg (68% containment, statistical error only), this was 20 deg from the LAT boresight at the time of the trigger.
  The Fermi LAT point of contact for this burst is Giacomo Vianello ( giacomov@stanford.edu).
  The Fermi LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden.
• GCN Circular #15588
  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,
  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
  V. Connaughton, M. S. Briggs, C. Meegan, V. Pelassa, and A. Goldstein, on behalf of the Fermi GBM team, report:
  The long-duration GRB 131209A (Vianello et al., GCN Circ. 15587) has been observed by Fermi (GBM: trigger 408287279), Konus-Wind, INTEGRAL (SPI-ACS), Swift (BAT), and MESSENGER (GRNS), so far, at about 47277 s UT (13:07:57). The burst was outside the coded field of view of the BAT.
  We have triangulated this GRB to a Konus-MESSENGER annulus centered at RA(2000)=64.917 deg (04h 19m 40s) Dec(2000)=+21.195 deg (+21d 11' 41"), whose radius is 87.724 +/- 0.105 deg (3 sigma).
  This annulus intersects the Fermi-LAT 1 sigma error circle (Vianello et al., GCN Circ. 15587) to form an error box whose area is about 16 times smaller than that of the LAT error circle (2.5 sq. deg.), and whose corners are:

    ---------------------------------------------
     RA(2000), deg                 Dec(2000), deg
    ---------------------------------------------
     Corners:
      137.365 (09h 09m 28s) -32.668 (-32d 40' 06")
      137.509 (09h 10m 02s) -32.892 (-32d 53' 32")
      136.780 (09h 07m 07s) -34.069 (-34d 04' 09")
      136.475 (09h 05m 54s) -34.100 (-34d 05' 59")
    ---------------------------------------------
  

  The error box area is 559 sq. arcmin, and its maximum dimension is 1.48 deg (the minimum one is 12.6 arcmin).
  This box may be improved.
  The distance between the annulus center line and the center of Fermi-LAT location is 0.5 deg.
  A triangulation map is posted at http://www.ioffe.ru/LEA/GRBs/GRB131209_T47280/IPN/
  The time history and spectrum will be given in forthcoming GCN Circulars.
• GCN Circular #15589
  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 131209A (Fermi LAT detection: Vianello & Omodei, GCN 15587; IPN triangulation: Hurley at al., GCN 15588) triggered Konus-Wind at T0=3D47280.491 s UT (13:08:00.491).
  The burst light curve shows a broad pulse from ~T0-3 s to ~T0+17 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/GRB131209_T47280/
  As observed by Konus-Wind, the burst had a fluence of (1.4 =B1 0.1)x10-5 erg/cm2, and a 64-ms peak flux, measured from T0+7.744 s, of (3.2 =B1 0.3)x10-6 erg/cm2/s (both in the 20 keV - 10 MeV energy range).
  The time-averaged spectrum (measured from T0 to T0+16.640 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 =3D -0.49 =B1 0.19, the high energy photon index beta =3D -2.68 =B1 0.46, the peak energy Ep =3D 235 =B1 29 keV, chi2 =3D 91.2/97 dof.
  The spectrum near the maximum count rate (measured from T0 to T0+8.448 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 =3D -0.17 =B1 0.17, the high energy photon index beta =3D -2.49 =B1 0.22, the peak energy Ep =3D 246 =B1 18 keV, chi2 =3D 87.2/97 dof.
  All the quoted values are preliminary.
• GCN Circular #15590
  P. A. Evans (U. Leicester) reports on behalf of the Swift team:
  Swift has initiated a series of observations, tiled on the sky, of the Fermi/LAT GRB 131209A. Automated analysis of the XRT data will be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00022
  Any uncatalogued X-ray sources detected in this analysis will be reported on this website and via GCN COUNTERPART notices. The probability of finding serendipitous sources, unrelated to the Fermi/LAT event is high: any X-ray source considered to be a probable afterglow candidate will be reported via a GCN Circular after manual consideration.
  Details of the XRT automated analysis methods are detailed in Evans et al. (2007, A&A, 469, 379; and 2009, MNRAS, 397, 1177).
  This circular is an official product of the Swift-XRT team.
• GCN Circular #15591
  A. von Kienlin (MPE) and C. Meegan (UAH) report on behalf of the Fermi GBM Team:
  "At 13:07:56.97 UT on 09 December 2013, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 131209A (trigger 408287279 / 131209547), which was also detected by the Fermi/LAT(Vianello et al. 2013, GCN 15587), Konus-Wind (Golenetskii et al. 2013, GCN 15589) and INTEGRAL SPI-ACS. The GBM on-ground location is consistent with the error box derived by the intersection of the IPN annulus with the Fermi-LAT 1 sigma error circle (Hurley et al. 2013, GCN 15588).
  The GBM light curve shows a structured pulse with a duration (T90) of about 14 s (50-300 keV). The time-averaged spectrum from T0-2.560 s to T0+19.968 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.46 (+0.04/-0.04) and the cutoff energy, parameterized as Epeak, is 287 (+12/-11)keV
  The event fluence (10-1000 keV) in this time interval is (1.44 +/- 0.03)E-05 erg/cm^2. The 1.024-sec peak photon flux measured starting from T0+11.328 s in the 10-1000 keV band is 8.0 +/- 0.3 ph/s/cm^2.
  A Band function fits the spectrum equally well with Epeak= 267 (+17/-14) keV, alpha = -0.41 (+0.06/-0.05) and beta = -2.79 (+0.24/-0.61).
  The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
• GCN Circular #15592
  Dirk Grupe (PSU) and Alice Breeveld (MSSL) report on behalf of the Swift team:
  We report on Swift observations of the field of the FERMI/LAT- discovered GRB 131209A (Vianello et al., GCN circ. 15587) starting 26.5 hours after the FERMI/LAT trigger. Swift performed three observations with and exposure tome of 3 ks each to cover most of the IPN error box reported by Hurley et al. (GCN circ. 15588). We found two X-ray sources with in the IPN error box, one of which coincides with a radio source, NVSS J090753-333724. The second source at the position

  RA-2000:   09 07 19.2 
  Dec-2000: -33 51 20.0
  

  does not have an entry in the NED or Simbad. Its count rate in the XRT is at a level of (4.7+/-1.9)e-3 counts/s which is equivalent to a flux in the 0.3-10 keV band of (1.9+/-0.7)e-13 erg/s/cm2. Swift started observing the tile that covered this source 33 hours after the Fermi/LAT trigger (Vianello et al., GCN Circ. 15587).
  Only one of the XRT potential candidate sources (source 2) is in the field of view of the UVOT and there is no new source found at this position. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the initial summed exposures are:

  Filter       T_start(hrs)   T_stop(hrs)   Exp(s)         Mag
  
  white        33.16          33.37          754         >21.8
  v            33.37          33.60          801         >20.1
  u            32.94          34.78         1367         >21.1
  

  The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.36 in the direction of the burst (Schlegel et al. 1998).
• GCN Circular #15683
  Dirk Grupe (Swift MOC, PSU) reports on behalf of the Swift team:
  We report on further Swift XRT observations of the field of the FERMI/LAT-discovered GRB 131209A (Vianello et al., GCN circ. 15587). As reported in GCN circular 15592 (Grupe & Breeveld) there was one uncatalogued X-ray source found within the IPN error box reported by Hurley et al. (GCN circ. 15588). We followed this source with Swift on 2013-December 17. This observation suggested a decaying source with a decay slope of about 1. Although this is a rather flat decay slope during the normal decay phase of a GRB X-ray afterglow, it is not uncommon (e.g. Grupe et al. 2013, ApJS, 209, 20). Nevertheless, it is also consistent with a variability by a factor of 2.5 which is quite common for an AGN (e.g. Grupe et al. 2010, ApJS, 187, 64). Therefore the data were not conclusive.
  We therefore performed two additional observations which were performed on 2014-January 02 and 03. During the 2014-January 02 observation the source had brightened again to a count rate in the XRT of (6.4+2.2-1.7)e-3 counts s^-1 and then dropped again down to (1.8+1.1-0.8)e-3 counts s^-1 during the January 03 observation. These observations suggest that the uncatalogued source in the IPN error box is not the X-ray afterglow of GRB 131209A. The rapid X-ray variability may suggest that this is either a Narrow Line Seyfert 1 Galaxy or a blazar if this is a background AGN.
  This report is an official product of the Swift team.