Gamma-ray Burst 171212B

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Tue 12 Dec 17 10:24:42 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      44
TRIGGER_NUM:     534767063
GRB_RA:           62.783d {+04h 11m 08s} (J2000),
                  62.775d {+04h 11m 06s} (current),
                  62.808d {+04h 11m 14s} (1950)
GRB_DEC:         -69.533d {-69d 31' 59"} (J2000),
                 -69.488d {-69d 29' 14"} (current),
                 -69.661d {-69d 39' 37"} (1950)
GRB_ERROR:       16.97 [deg radius, statistical plus systematic]
GRB_INTEN:       60 [cnts/sec]
DATA_SIGNIF:     5.10 [sigma]
INTEG_TIME:      4.096 [sec]
GRB_DATE:        18099 TJD;   346 DOY;   17/12/12
GRB_TIME:        37458.51 SOD {10:24:18.51} UT
GRB_PHI:           0.00 [deg]
GRB_THETA:         5.00 [deg]
DATA_TIME_SCALE: 4.0960 [sec]
HARD_RATIO:      2.09
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      74%  GRB
2nd_MOST_LIKELY:  22%  Generic SGR
DETECTORS:       1,0,0, 1,0,0, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:       259.76d {+17h 19m 02s}  -23.10d {-23d 06' 07"}
SUN_DIST:         86.60 [deg]   Sun_angle= -10.9 [hr] (East of Sun)
MOON_POSTN:      196.10d {+13h 04m 23s}   -2.12d {-02d 07' 03"}
MOON_DIST:       101.87 [deg]
MOON_ILLUM:      29 [%]
GAL_COORDS:      282.83,-38.87 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      331.35,-79.50 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2017/bn171212434/quicklook/glg_lc_medres34_bn171212434.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 219.72,-19.18 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Tue 12 Dec 17 10:24:52 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      57
TRIGGER_NUM:     534767063
GRB_RA:           63.133d {+04h 12m 32s} (J2000),
                  63.123d {+04h 12m 30s} (current),
                  63.165d {+04h 12m 40s} (1950)
GRB_DEC:         -69.650d {-69d 39' 00"} (J2000),
                 -69.605d {-69d 36' 16"} (current),
                 -69.776d {-69d 46' 32"} (1950)
GRB_ERROR:       12.20 [deg radius, statistical plus systematic]
GRB_INTEN:       85 [cnts/sec]
DATA_SIGNIF:     7.60 [sigma]
INTEG_TIME:      4.096 [sec]
GRB_DATE:        18099 TJD;   346 DOY;   17/12/12
GRB_TIME:        37458.51 SOD {10:24:18.51} UT
GRB_PHI:           0.00 [deg]
GRB_THETA:         5.00 [deg]
DATA_TIME_SCALE: 4.0960 [sec]
HARD_RATIO:      1.87
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      85%  GRB
2nd_MOST_LIKELY:  14%  Generic SGR
DETECTORS:       1,0,0, 1,0,0, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:       259.76d {+17h 19m 02s}  -23.10d {-23d 06' 07"}
SUN_DIST:         86.52 [deg]   Sun_angle= -10.9 [hr] (East of Sun)
MOON_POSTN:      196.10d {+13h 04m 23s}   -2.12d {-02d 07' 05"}
MOON_DIST:       101.70 [deg]
MOON_ILLUM:      29 [%]
GAL_COORDS:      282.89,-38.71 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      330.66,-79.61 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2017/bn171212434/quicklook/glg_lc_medres34_bn171212434.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 219.72,-19.18 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Tue 12 Dec 17 10:24:57 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      56
TRIGGER_NUM:     534767063
GRB_RA:           49.130d {+03h 16m 31s} (J2000),
                  49.161d {+03h 16m 39s} (current),
                  49.048d {+03h 16m 12s} (1950)
GRB_DEC:         -69.270d {-69d 16' 11"} (J2000),
                 -69.205d {-69d 12' 16"} (current),
                 -69.452d {-69d 27' 07"} (1950)
GRB_ERROR:       4.54 [deg radius, statistical only]
DATA_SIGNIF:     8.60 [sigma]
DATA_INTERVAL:   4.096 [sec]
GRB_DATE:        18099 TJD;   346 DOY;   17/12/12
GRB_TIME:        37458.51 SOD {10:24:18.51} UT
GRB_PHI:         324.00 [deg]
GRB_THETA:         8.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4153 (Gnd S/W Version number)
SUN_POSTN:       259.76d {+17h 19m 02s}  -23.10d {-23d 06' 07"}
SUN_DIST:         85.08 [deg]   Sun_angle= -10.0 [hr] (East of Sun)
MOON_POSTN:      196.10d {+13h 04m 23s}   -2.12d {-02d 07' 06"}
MOON_DIST:       105.24 [deg]
MOON_ILLUM:      29 [%]
GAL_COORDS:      286.33,-42.88 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      331.37,-74.70 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2017/bn171212434/quicklook/glg_lc_medres34_bn171212434.gif
POS_MAP_URL:     http://gcn.gsfc.nasa.gov/notices_f/gbm_gnd_loc_map_534767063.fits
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        In the LAT Field-of-view.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        The LC_URL file will not be created/available until ~15 min after the trigger.  
COMMENTS:        The POS_MAP_URL file will not be created/available until ~1.5 min after the notice.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Tue 12 Dec 17 10:25:06 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      68
TRIGGER_NUM:     534767063
GRB_RA:           29.383d {+01h 57m 32s} (J2000),
                  29.472d {+01h 57m 53s} (current),
                  29.137d {+01h 56m 33s} (1950)
GRB_DEC:         -70.850d {-70d 50' 59"} (J2000),
                 -70.763d {-70d 45' 46"} (current),
                 -71.093d {-71d 05' 33"} (1950)
GRB_ERROR:       8.83 [deg radius, statistical plus systematic]
GRB_INTEN:       146 [cnts/sec]
DATA_SIGNIF:     13.10 [sigma]
INTEG_TIME:      4.096 [sec]
GRB_DATE:        18099 TJD;   346 DOY;   17/12/12
GRB_TIME:        37458.51 SOD {10:24:18.51} UT
GRB_PHI:         320.00 [deg]
GRB_THETA:        15.00 [deg]
DATA_TIME_SCALE: 4.0960 [sec]
HARD_RATIO:      1.12
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      98%  GRB
2nd_MOST_LIKELY:   1%  Generic SGR
DETECTORS:       1,0,0, 1,0,0, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:       259.76d {+17h 19m 02s}  -23.10d {-23d 06' 07"}
SUN_DIST:         79.82 [deg]   Sun_angle= -8.6 [hr] (East of Sun)
MOON_POSTN:      196.10d {+13h 04m 24s}   -2.12d {-02d 07' 07"}
MOON_DIST:       106.58 [deg]
MOON_ILLUM:      29 [%]
GAL_COORDS:      295.31,-45.29 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      321.41,-68.55 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2017/bn171212434/quicklook/glg_lc_medres34_bn171212434.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 219.72,-19.18 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.

GCN Circular #22247
D. Kocevski (NASA/MSFC), F. Longo (Univ & INFN Trieste), E. Bissaldi (Politecnico & INFN Bari), and G. Vianello (Stanford)
report on behalf of the Fermi-LAT team:
At 10:24:18.51 UT on December 12, 2017, Fermi-LAT detected high-energy emission from GRB 171212B, which was also detected by Fermi-GBM (trigger 534767063 / 171212434).
The best LAT on-ground location is found to be
RA, Dec = 39.44, -70.62 (J2000)
with an error radius of 0.39 deg (90 % containment, statistical error only).
This was 11 deg from the LAT boresight at the time of the trigger.
The data from the Fermi-LAT show a significant increase in the event rate that is spatially correlated with the trigger with high significance. The highest-energy photon is a 931 MeV event which is observed 544 seconds after the GBM trigger.
The Fermi-LAT point of contact for this burst is Francesco Longo (francesco.longo@ts.infn.it).
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 #22249
E. Bissaldi (Politecnico & INFN Bari) and C. Meegan (UAH) report on behalf of the Fermi GBM Team:
"At 10:24:18.51 UT on 12 December 2017, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 171212B (trigger 534767063 / 171212434), which was also detected by the Fermi-LAT (Kocevski et al. 2012, GCN 22247). The GBM on-ground location is consistent with the LAT position.
The angle from the Fermi LAT boresight at the GBM trigger time is 11 degrees.
The GBM light curve consists of a multipeak emission episode with a duration (T90) of about 32 s (50-300 keV). The time-averaged spectrum from T0 to T0+32 s is adequately fit by a Band function with Epeak = 74 +/- 9 keV, alpha = -0.95 +/- 0.13, and beta = -2.32 +/- 0.15.
The event fluence (10-1000 keV) in this time interval is (5.744 +/- 0.3)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0+27 s in the 10-1000 keV band is 5.0 +/- 0.3 ph/s/cm^2.
The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."

Back to JG's homepage

Jochen Greiner, last update: 12-Dec-2017 [Disclaimer]