Gamma-ray Burst 161004B

(All information courtesy of the instrument teams.)

Previous IAU Circulars

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Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 04 Oct 16 23:08:24 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     715246,   Seg_Num: 0
GRB_RA:          112.157d {+07h 28m 38s} (J2000),
                 112.300d {+07h 29m 12s} (current),
                 111.732d {+07h 26m 56s} (1950)
GRB_DEC:         -39.895d {-39d 53' 40"} (J2000),
                 -39.930d {-39d 55' 47"} (current),
                 -39.791d {-39d 47' 25"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       11049 [cnts]    Image_Peak=1856 [image_cnts]
TRIGGER_DUR:     1.024 [sec] 
TRIGGER_INDEX:   146     E_range: 25-100 keV
BKG_INTEN:       20795 [cnts]
BKG_TIME:        83263.04 SOD {23:07:43.04} UT
BKG_DUR:         8 [sec]
GRB_DATE:        17665 TJD;   278 DOY;   16/10/04
GRB_TIME:        83279.29 SOD {23:07:59.29} UT
GRB_PHI:         -50.79 [deg]
GRB_THETA:        26.62 [deg]
SOLN_STATUS:     0x20000003
RATE_SIGNIF:     152.83 [sigma]
IMAGE_SIGNIF:    24.22 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +2  +8  +0  +0 -20  +0 
SUN_POSTN:       191.18d {+12h 44m 42s}   -4.80d {-04d 48' 06"}
SUN_DIST:         78.39 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      234.42d {+15h 37m 42s}  -14.30d {-14d 17' 57"}
MOON_DIST:       103.69 [deg]
MOON_ILLUM:      14 [%]
GAL_COORDS:      252.58,-10.49 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      126.10,-60.59 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Coordinates.  
COMMENTS:        This is a rate trigger.  
COMMENTS:        A point_source was found.  
COMMENTS:        This does not match any source in the on-board catalog.  
COMMENTS:        This does not match any source in the ground catalog.  
COMMENTS:        This is a GRB.  
COMMENTS:        This trigger occurred at longitude,latitude = 59.15,-17.68 [deg].  
COMMENTS:           
COMMENTS:        NOTE: This BAT event is temporally(7.0<100sec) coincident with the CALET_GBM event (trignum=1159657616).

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Tue 04 Oct 16 23:08:00 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      47
TRIGGER_NUM:     497315278
GRB_RA:          102.667d {+06h 50m 40s} (J2000),
                 102.833d {+06h 51m 20s} (current),
                 102.170d {+06h 48m 41s} (1950)
GRB_DEC:         -27.867d {-27d 52' 00"} (J2000),
                 -27.887d {-27d 53' 13"} (current),
                 -27.807d {-27d 48' 24"} (1950)
GRB_ERROR:       8.82 [deg radius, statistical plus systematic]
GRB_INTEN:       269 [cnts/sec]
DATA_SIGNIF:     12.90 [sigma]
INTEG_TIME:      1.024 [sec]
GRB_DATE:        17665 TJD;   278 DOY;   16/10/04
GRB_TIME:        83274.79 SOD {23:07:54.79} UT
GRB_PHI:         292.00 [deg]
GRB_THETA:        55.00 [deg]
DATA_TIME_SCALE: 1.0240 [sec]
HARD_RATIO:      0.50
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      95%  GRB
2nd_MOST_LIKELY:   4%  Generic Transient
DETECTORS:       0,0,0, 0,1,0, 0,1,0, 0,0,0, 0,0,
SUN_POSTN:       191.17d {+12h 44m 42s}   -4.80d {-04d 48' 05"}
SUN_DIST:         86.29 [deg]   Sun_angle= 5.9 [hr] (West of Sun)
MOON_POSTN:      234.42d {+15h 37m 41s}  -14.30d {-14d 17' 55"}
MOON_DIST:       116.93 [deg]
MOON_ILLUM:      14 [%]
GAL_COORDS:      238.06,-12.46 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      107.75,-50.53 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2016/bn161004964/quicklook/glg_lc_medres34_bn161004964.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 127.73,-4.03 [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 04 Oct 16 23:08:06 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      58
TRIGGER_NUM:     497315278
GRB_RA:          103.567d {+06h 54m 16s} (J2000),
                 103.722d {+06h 54m 53s} (current),
                 103.102d {+06h 52m 25s} (1950)
GRB_DEC:         -33.083d {-33d 04' 59"} (J2000),
                 -33.105d {-33d 06' 18"} (current),
                 -33.019d {-33d 01' 08"} (1950)
GRB_ERROR:       4.40 [deg radius, statistical plus systematic]
GRB_INTEN:       882 [cnts/sec]
DATA_SIGNIF:     61.20 [sigma]
INTEG_TIME:      2.048 [sec]
GRB_DATE:        17665 TJD;   278 DOY;   16/10/04
GRB_TIME:        83274.79 SOD {23:07:54.79} UT
GRB_PHI:         290.00 [deg]
GRB_THETA:        60.00 [deg]
DATA_TIME_SCALE: 2.0480 [sec]
HARD_RATIO:      0.68
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      96%  GRB
2nd_MOST_LIKELY:   3%  Generic Transient
DETECTORS:       0,0,0, 0,1,0, 0,1,0, 0,0,0, 0,0,
SUN_POSTN:       191.18d {+12h 44m 42s}   -4.80d {-04d 48' 06"}
SUN_DIST:         85.25 [deg]   Sun_angle= 5.8 [hr] (West of Sun)
MOON_POSTN:      234.42d {+15h 37m 41s}  -14.30d {-14d 17' 55"}
MOON_DIST:       113.23 [deg]
MOON_ILLUM:      14 [%]
GAL_COORDS:      243.28,-13.87 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      110.34,-55.57 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2016/bn161004964/quicklook/glg_lc_medres34_bn161004964.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 127.73,-4.03 [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 04 Oct 16 23:08:10 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      56
TRIGGER_NUM:     497315278
GRB_RA:          112.620d {+07h 30m 29s} (J2000),
                 112.770d {+07h 31m 05s} (current),
                 112.172d {+07h 28m 41s} (1950)
GRB_DEC:         -36.840d {-36d 50' 23"} (J2000),
                 -36.876d {-36d 52' 33"} (current),
                 -36.734d {-36d 44' 01"} (1950)
GRB_ERROR:       1.50 [deg radius, statistical only]
DATA_SIGNIF:     58.30 [sigma]
DATA_INTERVAL:   4.096 [sec]
GRB_DATE:        17665 TJD;   278 DOY;   16/10/04
GRB_TIME:        83274.79 SOD {23:07:54.79} UT
GRB_PHI:         295.00 [deg]
GRB_THETA:        67.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4153 (Gnd S/W Version number)
SUN_POSTN:       191.18d {+12h 44m 42s}   -4.80d {-04d 48' 06"}
SUN_DIST:         77.85 [deg]   Sun_angle= 5.2 [hr] (West of Sun)
MOON_POSTN:      234.42d {+15h 37m 41s}  -14.30d {-14d 17' 56"}
MOON_DIST:       104.98 [deg]
MOON_ILLUM:      14 [%]
GAL_COORDS:      249.98, -8.78 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      125.02,-57.56 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2016/bn161004964/quicklook/glg_lc_medres34_bn161004964.gif
POS_MAP_URL:     http://gcn.gsfc.nasa.gov/notices_f/gbm_gnd_loc_map_497315278.fits
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
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/INTEGRAL NOTICE
NOTICE_DATE:    Tue 04 Oct 16 23:08:58 UT
NOTICE_TYPE:    INTEGRAL SPI ACS Trigger
TRIGGER_NUM:    7590,   Sub_Num: 0
GRB_INTEN:      9.41 [sigma]
GRB_TIME:       83273.95 SOD {23:07:53.95} UT
GRB_DATE:       17665 TJD;   278 DOY;   16/10/04
COMMENTS:       INTEGRAL SPI_ACS GRB Trigger.
COMMENTS:       Time_Scale=2.0000 and Time_Error=1.0000.  
COMMENTS:
COMMENTS:       NOTE: This SPIACS event is temporally(6.0<100sec) coincident with the SWIFT_BAT event (trignum=715246).
COMMENTS:
COMMENTS:       The SPIACS lightcurve can be found at:
COMMENTS:       ftp://isdcarc.unige.ch/arc/FTP/ibas/spiacs/2016-10/2016-10-04T23-07-53.8644-03881-39824-0.lc

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 04 Oct 16 23:09:55 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     715246,   Seg_Num: 0
GRB_RA:          112.1500d {+07h 28m 36.00s} (J2000),
                 112.2925d {+07h 29m 10.19s} (current),
                 111.7250d {+07h 26m 53.99s} (1950)
GRB_DEC:         -39.8972d {-39d 53' 49.9"} (J2000),
                 -39.9325d {-39d 55' 56.9"} (current),
                 -39.7932d {-39d 47' 35.4"} (1950)
GRB_ERROR:       6.3 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       5.23e-10 [erg/cm2/sec]
GRB_SIGNIF:      4.58 [sigma]
IMG_START_DATE:  17665 TJD;   278 DOY;   16/10/04
IMG_START_TIME:  83352.73 SOD {23:09:12.73} UT,   73.4 [sec] since BAT Trigger Time
TAM[0-3]:        327.64 237.18 261.55 243.72
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       191.18d {+12h 44m 42s}   -4.80d {-04d 48' 07"}
SUN_DIST:         78.40 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      234.44d {+15h 37m 45s}  -14.30d {-14d 18' 06"}
MOON_DIST:       103.70 [deg]
MOON_ILLUM:      14 [%]
GAL_COORDS:      252.58,-10.50 [deg] galactic lon,lat of the burst
ECL_COORDS:      126.09,-60.59 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 0.37 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 04 Oct 16 23:10:07 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     715246,   Seg_Num: 0
GRB_RA:          112.1500d {+07h 28m 36.0s} (J2000),
                 112.2925d {+07h 29m 10.1s} (current),
                 111.7250d {+07h 26m 53.9s} (1950)
GRB_DEC:         -39.8972d {-39d 53' 49.9"} (J2000),
                 -39.9325d {-39d 55' 56.9"} (current),
                 -39.7932d {-39d 47' 35.4"} (1950)
GRB_ERROR:       6.1 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       21 [cnts]
IMG_START_DATE:  17665 TJD;   278 DOY;   16/10/04
IMG_START_TIME:  83352.73 SOD {23:09:12.73} UT,   73.4 [sec] since BAT Trigger Time
CENTROID_X:      297.27,  raw= 297  [pixels]
CENTROID_Y:      290.52,  raw= 291  [pixels]
ROLL:            86.66 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -17.14
GRB_POS_XRT_Z:   -18.91
IMAGE_URL:       sw00715246000msxps_rw.img
SUN_POSTN:       191.18d {+12h 44m 42s}   -4.80d {-04d 48' 07"}
SUN_DIST:         78.40 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      234.44d {+15h 37m 45s}  -14.30d {-14d 18' 08"}
MOON_DIST:       103.70 [deg]
MOON_ILLUM:      14 [%]
GAL_COORDS:      252.58,-10.50 [deg] galactic lon,lat of the burst
ECL_COORDS:      126.09,-60.59 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 04 Oct 16 23:10:14 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     715246,   Seg_Num: 0
GRB_RA:          112.1500d {+07h 28m 36.0s} (J2000),
                 112.2925d {+07h 29m 10.1s} (current),
                 111.7250d {+07h 26m 53.9s} (1950)
GRB_DEC:         -39.8972d {-39d 53' 49.9"} (J2000),
                 -39.9325d {-39d 55' 56.9"} (current),
                 -39.7932d {-39d 47' 35.4"} (1950)
GRB_ERROR:       6.1 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       21 [cnts]
IMG_START_DATE:  17665 TJD;   278 DOY;   16/10/04
IMG_START_TIME:  83352.73 SOD {23:09:12.73} UT,   73.4 [sec] since BAT Trigger Time
CENTROID_X:      297.27,  raw= 297  [pixels]
CENTROID_Y:      290.52,  raw= 291  [pixels]
ROLL:            86.66 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -17.14
GRB_POS_XRT_Z:   -18.91
IMAGE_URL:       sw00715246000msxps_rw.img
SUN_POSTN:       191.18d {+12h 44m 42s}   -4.80d {-04d 48' 08"}
SUN_DIST:         78.40 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      234.44d {+15h 37m 45s}  -14.30d {-14d 18' 08"}
MOON_DIST:       103.70 [deg]
MOON_ILLUM:      14 [%]
GAL_COORDS:      252.58,-10.50 [deg] galactic lon,lat of the burst
ECL_COORDS:      126.09,-60.59 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 04 Oct 16 23:11:52 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     715246,   Seg_Num: 0
GRB_RA:          112.157d {+07h 28m 38s} (J2000),
                 112.300d {+07h 29m 12s} (current),
                 111.732d {+07h 26m 56s} (1950)
GRB_DEC:         -39.895d {-39d 53' 40"} (J2000),
                 -39.930d {-39d 55' 47"} (current),
                 -39.791d {-39d 47' 25"} (1950)
GRB_DATE:        17665 TJD;   278 DOY;   16/10/04
GRB_TIME:        83279.29 SOD {23:07:59.29} UT
TRIGGER_INDEX:   146
GRB_PHI:         -50.79 [deg]
GRB_THETA:        26.62 [deg]
DELTA_TIME:      -24.00 [sec]
TRIGGER_DUR:     1.024 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     152.83 [sigma]
IMAGE_SIGNIF:    24.22 [sigma]
LC_URL:          sw00715246000msb.lc
SUN_POSTN:       191.18d {+12h 44m 43s}   -4.80d {-04d 48' 09"}
SUN_DIST:         78.40 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      234.45d {+15h 37m 48s}  -14.31d {-14d 18' 18"}
MOON_DIST:       103.70 [deg]
MOON_ILLUM:      14 [%]
GAL_COORDS:      252.58,-10.49 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      126.10,-60.59 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Lightcurve.  
COMMENTS:           
COMMENTS:        The next comments were copied from the BAT_POS Notice:  
COMMENTS:        This is a rate trigger.  
COMMENTS:        A point_source was found.  
COMMENTS:        This does not match any source in the on-board catalog.  
COMMENTS:        This does not match any source in the ground catalog.  
COMMENTS:        This is a GRB.  
COMMENTS:        This trigger occurred at longitude,latitude = 59.15,-17.68 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 04 Oct 16 23:12:44 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     715246,   Seg_Num: 0
POINT_RA:        112.143d {+07h 28m 34s} (J2000)
POINT_DEC:       -39.893d {-39d 53' 33"} (J2000)
POINT_ROLL:      86.657d
IMG_START_DATE:  17665 TJD;   278 DOY;   16/10/04
IMG_START_TIME:  83361.60 SOD {23:09:21.60} UT,   82.3 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.142
N_STARS:         111
X_OFFSET:        568 [pixels]
Y_OFFSET:        536 [pixels]
X_MAX:           1527 [pixels]
Y_MAX:           1495 [pixels]
DET_THRESH:      15
PHOTO_THRESH:    8
SL_URL:          sw00715246000msufc0082.fits
SUN_POSTN:       191.18d {+12h 44m 43s}   -4.80d {-04d 48' 10"}
SUN_DIST:         78.41 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      234.46d {+15h 37m 50s}  -14.31d {-14d 18' 24"}
MOON_DIST:       103.71 [deg]
MOON_ILLUM:      14 [%]
GAL_COORDS:      252.57,-10.50 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      126.08,-60.59 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 04 Oct 16 23:13:34 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     715246,   Seg_Num: 0
POINT_RA:        112.143d {+07h 28m 34s} (J2000)
POINT_DEC:       -39.893d {-39d 53' 33"} (J2000)
POINT_ROLL:      86.657d
IMG_START_DATE:  17665 TJD;   278 DOY;   16/10/04
IMG_START_TIME:  83361.60 SOD {23:09:21.60} UT,   82.3 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.142
N_STARS:         111
X_OFFSET:        568 [pixels]
Y_OFFSET:        536 [pixels]
X_MAX:           1527 [pixels]
Y_MAX:           1495 [pixels]
DET_THRESH:      15
PHOTO_THRESH:    8
SL_URL:          sw00715246000msufc0082.fits
SUN_POSTN:       191.18d {+12h 44m 43s}   -4.80d {-04d 48' 11"}
SUN_DIST:         78.41 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      234.47d {+15h 37m 52s}  -14.31d {-14d 18' 29"}
MOON_DIST:       103.72 [deg]
MOON_ILLUM:      14 [%]
GAL_COORDS:      252.57,-10.50 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      126.08,-60.59 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 04 Oct 16 23:14:08 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     715246,   Seg_Num: 0
POINT_RA:        112.143d {+07h 28m 34s} (J2000)
POINT_DEC:       -39.893d {-39d 53' 33"} (J2000)
ROLL:            86.657d
IMG_START_DATE:  17665 TJD;   278 DOY;   16/10/04
IMG_START_TIME:  83361.60 SOD {23:09:21.60} UT,   82.3 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     497315378
X_OFFSET:        862 [pixels]
Y_OFFSET:        886 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1022
Y_GRB_POS:       1046
BINNING_INDEX:   1
IM_URL:          sw00715246000msuni0099.fits
SUN_POSTN:       191.18d {+12h 44m 43s}   -4.80d {-04d 48' 11"}
SUN_DIST:         78.41 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      234.47d {+15h 37m 53s}  -14.31d {-14d 18' 32"}
MOON_DIST:       103.72 [deg]
MOON_ILLUM:      14 [%]
GAL_COORDS:      252.57,-10.50 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      126.08,-60.59 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 04 Oct 16 23:14:36 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     715246,   Seg_Num: 0
POINT_RA:        112.143d {+07h 28m 34s} (J2000)
POINT_DEC:       -39.893d {-39d 53' 33"} (J2000)
ROLL:            86.657d
IMG_START_DATE:  17665 TJD;   278 DOY;   16/10/04
IMG_START_TIME:  83361.60 SOD {23:09:21.60} UT,   82.3 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     497315378
X_OFFSET:        862 [pixels]
Y_OFFSET:        886 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1022
Y_GRB_POS:       1046
BINNING_INDEX:   1
IM_URL:          sw00715246000msuni0099.fits
SUN_POSTN:       191.18d {+12h 44m 43s}   -4.80d {-04d 48' 12"}
SUN_DIST:         78.41 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      234.47d {+15h 37m 54s}  -14.31d {-14d 18' 35"}
MOON_DIST:       103.72 [deg]
MOON_ILLUM:      14 [%]
GAL_COORDS:      252.57,-10.50 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      126.08,-60.59 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        All 4 attachments are included.

GCN Circular #19987
A. D'Ai (INAF-IASFPA), V. D'Elia (ASDC), F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL) and B. Sbarufatti (INAF-OAB/PSU) report on behalf of the Swift Team:
At 23:07:59 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 161004B (trigger=715246). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 112.157, -39.895 which is
```
   RA(J2000) = 07h 28m 38s
   Dec(J2000) = -39d 53' 40"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single FRED peak with substructure and a duration of about 20 sec. The peak count rate was ~12000 counts/sec (15-350 keV), at ~1 sec after the trigger.
The XRT began observing the field at 23:09:12.7 UT, 73.4 seconds after the BAT trigger. Using promptly downlinked data we find a bright, uncatalogued X-ray source located at RA, Dec 112.15290, -39.89858 which is equivalent to:
```
   RA(J2000)  = 07h 28m 36.70s
   Dec(J2000) = -39d 53' 54.9"
```
with an uncertainty of 3.6 arcseconds (radius, 90% containment). This location is 17 arcseconds from the BAT onboard position, within the BAT error circle. This position may be improved as more data are received; the latest position is available at http://www.swift.ac.uk/sper. We cannot determine whether the source is fading at the present time. No spectrum from the promptly downlinked event data is yet available to determine the column density.
The initial flux in the 2.5 s image was 5.23e-10 erg cm^-2 s^-1 (0.2-10 keV).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 82 seconds after the BAT trigger. No credible afterglow candidate has been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. The 8'x8' region for the list of sources generated on-board covers 100% of the XRT error circle. The list of sources is typically complete to about 18 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.54.
Burst Advocate for this burst is A. D'Ai (antonino.dai AT ifc.inaf.it). Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/too.html.)
GCN Circular #19988

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 04 Oct 16 23:21:45 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     715246,   Seg_Num: 0
POINT_RA:        112.140d {+07h 28m 34s} (J2000)
POINT_DEC:       -39.892d {-39d 53' 29"} (J2000)
POINT_ROLL:      86.660d
IMG_START_DATE:  17665 TJD;   278 DOY;   16/10/04
IMG_START_TIME:  83573.60 SOD {23:12:53.60} UT,   294.3 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.173
N_STARS:         60
X_OFFSET:        542 [pixels]
Y_OFFSET:        566 [pixels]
X_MAX:           1501 [pixels]
Y_MAX:           1525 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00715246000msufc0294.fits
SUN_POSTN:       191.18d {+12h 44m 44s}   -4.81d {-04d 48' 19"}
SUN_DIST:         78.41 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      234.53d {+15h 38m 08s}  -14.32d {-14d 19' 19"}
MOON_DIST:       103.75 [deg]
MOON_ILLUM:      14 [%]
GAL_COORDS:      252.57,-10.50 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      126.07,-60.59 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 04 Oct 16 23:21:33 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     715246,   Seg_Num: 0
POINT_RA:        112.140d {+07h 28m 34s} (J2000)
POINT_DEC:       -39.892d {-39d 53' 29"} (J2000)
POINT_ROLL:      86.660d
IMG_START_DATE:  17665 TJD;   278 DOY;   16/10/04
IMG_START_TIME:  83573.60 SOD {23:12:53.60} UT,   294.3 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.173
N_STARS:         60
X_OFFSET:        542 [pixels]
Y_OFFSET:        566 [pixels]
X_MAX:           1501 [pixels]
Y_MAX:           1525 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00715246000msufc0294.fits
SUN_POSTN:       191.18d {+12h 44m 44s}   -4.81d {-04d 48' 18"}
SUN_DIST:         78.41 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      234.53d {+15h 38m 08s}  -14.32d {-14d 19' 17"}
MOON_DIST:       103.75 [deg]
MOON_ILLUM:      14 [%]
GAL_COORDS:      252.57,-10.50 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      126.07,-60.59 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 04 Oct 16 23:22:34 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     715246,   Seg_Num: 0
POINT_RA:        112.140d {+07h 28m 34s} (J2000)
POINT_DEC:       -39.892d {-39d 53' 29"} (J2000)
ROLL:            86.660d
IMG_START_DATE:  17665 TJD;   278 DOY;   16/10/04
IMG_START_TIME:  83573.60 SOD {23:12:53.60} UT,   294.3 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     497315590
X_OFFSET:        862 [pixels]
Y_OFFSET:        886 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1022
Y_GRB_POS:       1046
BINNING_INDEX:   1
IM_URL:          sw00715246000msuni0311.fits
SUN_POSTN:       191.18d {+12h 44m 44s}   -4.81d {-04d 48' 19"}
SUN_DIST:         78.41 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      234.54d {+15h 38m 10s}  -14.32d {-14d 19' 24"}
MOON_DIST:       103.76 [deg]
MOON_ILLUM:      14 [%]
GAL_COORDS:      252.57,-10.50 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      126.07,-60.59 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 04 Oct 16 23:22:48 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     715246,   Seg_Num: 0
GRB_RA:          112.1514d {+07h 28m 36.33s} (J2000),
                 112.2939d {+07h 29m 10.53s} (current),
                 111.7264d {+07h 26m 54.33s} (1950)
GRB_DEC:         -39.8980d {-39d 53' 52.8"} (J2000),
                 -39.9333d {-39d 55' 59.8"} (current),
                 -39.7940d {-39d 47' 38.3"} (1950)
GRB_ERROR:       2.1 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  17665 TJD;   278 DOY;   16/10/04
IMG_START_TIME:  83438.00 SOD {23:10:38.00} UT,   158.7 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       191.18d {+12h 44m 44s}   -4.81d {-04d 48' 20"}
SUN_DIST:         78.40 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      234.54d {+15h 38m 10s}  -14.32d {-14d 19' 25"}
MOON_DIST:       103.75 [deg]
MOON_ILLUM:      14 [%]
GAL_COORDS:      252.58,-10.50 [deg] galactic lon,lat of the burst
ECL_COORDS:      126.09,-60.59 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        This is an Update Notice -- the RA,Dec values herein supersede the previous XRT_POS Notice.  
COMMENTS:        TAM values, flux and significance fields are not valid.  
COMMENTS:        This position was automatically generated on the ground using  
COMMENTS:        Photon Counting data telemetered via TDRSS (SPER data).  
COMMENTS:        See http://www.swift.ac.uk/sper/docs.php for details.  
COMMENTS:        This position was enhanced using UVOT field astrometry.  
COMMENTS:        The probability that this is a serendipitous source in the  
COMMENTS:        SPER window is 0.11% < P(seren) < 0.58%.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 04 Oct 16 23:22:51 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     715246,   Seg_Num: 0
POINT_RA:        112.140d {+07h 28m 34s} (J2000)
POINT_DEC:       -39.892d {-39d 53' 29"} (J2000)
ROLL:            86.660d
IMG_START_DATE:  17665 TJD;   278 DOY;   16/10/04
IMG_START_TIME:  83573.60 SOD {23:12:53.60} UT,   294.3 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     497315590
X_OFFSET:        862 [pixels]
Y_OFFSET:        886 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1022
Y_GRB_POS:       1046
BINNING_INDEX:   1
IM_URL:          sw00715246000msuni0311.fits
SUN_POSTN:       191.18d {+12h 44m 44s}   -4.81d {-04d 48' 20"}
SUN_DIST:         78.41 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      234.54d {+15h 38m 10s}  -14.32d {-14d 19' 25"}
MOON_DIST:       103.76 [deg]
MOON_ILLUM:      14 [%]
GAL_COORDS:      252.57,-10.50 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      126.07,-60.59 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 04 Oct 16 23:28:40 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     715246,   Seg_Num: 0
POINT_RA:        112.140d {+07h 28m 34s} (J2000)
POINT_DEC:       -39.892d {-39d 53' 29"} (J2000)
POINT_ROLL:      86.660d
IMG_START_DATE:  17665 TJD;   278 DOY;   16/10/04
IMG_START_TIME:  84151.26 SOD {23:22:31.26} UT,   872.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.618
N_STARS:         190
X_OFFSET:        302 [pixels]
Y_OFFSET:        326 [pixels]
X_MAX:           1741 [pixels]
Y_MAX:           1765 [pixels]
DET_THRESH:      16
PHOTO_THRESH:    9
SL_URL:          sw00715246000msufc0871.fits
SUN_POSTN:       191.19d {+12h 44m 45s}   -4.81d {-04d 48' 25"}
SUN_DIST:         78.41 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      234.59d {+15h 38m 22s}  -14.33d {-14d 20' 01"}
MOON_DIST:       103.78 [deg]
MOON_ILLUM:      14 [%]
GAL_COORDS:      252.57,-10.50 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      126.07,-60.59 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 04 Oct 16 23:28:58 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     715246,   Seg_Num: 0
POINT_RA:        112.140d {+07h 28m 34s} (J2000)
POINT_DEC:       -39.892d {-39d 53' 29"} (J2000)
POINT_ROLL:      86.660d
IMG_START_DATE:  17665 TJD;   278 DOY;   16/10/04
IMG_START_TIME:  84151.26 SOD {23:22:31.26} UT,   872.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.618
N_STARS:         190
X_OFFSET:        302 [pixels]
Y_OFFSET:        326 [pixels]
X_MAX:           1741 [pixels]
Y_MAX:           1765 [pixels]
DET_THRESH:      16
PHOTO_THRESH:    9
SL_URL:          sw00715246000msufc0871.fits
SUN_POSTN:       191.19d {+12h 44m 45s}   -4.81d {-04d 48' 26"}
SUN_DIST:         78.41 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      234.59d {+15h 38m 22s}  -14.33d {-14d 20' 03"}
MOON_DIST:       103.78 [deg]
MOON_ILLUM:      14 [%]
GAL_COORDS:      252.57,-10.50 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      126.07,-60.59 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 04 Oct 16 23:29:05 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     715246,   Seg_Num: 0
POINT_RA:        112.140d {+07h 28m 34s} (J2000)
POINT_DEC:       -39.892d {-39d 53' 29"} (J2000)
ROLL:            86.660d
IMG_START_DATE:  17665 TJD;   278 DOY;   16/10/04
IMG_START_TIME:  84151.26 SOD {23:22:31.26} UT,   872.0 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     497316168
X_OFFSET:        861 [pixels]
Y_OFFSET:        885 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1021
Y_GRB_POS:       1045
BINNING_INDEX:   1
IM_URL:          sw00715246000msuni0888.fits
SUN_POSTN:       191.19d {+12h 44m 45s}   -4.81d {-04d 48' 26"}
SUN_DIST:         78.41 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      234.59d {+15h 38m 23s}  -14.33d {-14d 20' 03"}
MOON_DIST:       103.78 [deg]
MOON_ILLUM:      14 [%]
GAL_COORDS:      252.57,-10.50 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      126.07,-60.59 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Image.  
COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
COMMENTS:        The image has 2x2 binning (compression).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 04 Oct 16 23:29:21 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     715246,   Seg_Num: 0
POINT_RA:        112.140d {+07h 28m 34s} (J2000)
POINT_DEC:       -39.892d {-39d 53' 29"} (J2000)
ROLL:            86.660d
IMG_START_DATE:  17665 TJD;   278 DOY;   16/10/04
IMG_START_TIME:  84151.26 SOD {23:22:31.26} UT,   872.0 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     497316168
X_OFFSET:        861 [pixels]
Y_OFFSET:        885 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1021
Y_GRB_POS:       1045
BINNING_INDEX:   1
IM_URL:          sw00715246000msuni0888.fits
SUN_POSTN:       191.19d {+12h 44m 45s}   -4.81d {-04d 48' 26"}
SUN_DIST:         78.41 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      234.60d {+15h 38m 23s}  -14.33d {-14d 20' 05"}
MOON_DIST:       103.78 [deg]
MOON_ILLUM:      14 [%]
GAL_COORDS:      252.57,-10.50 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      126.07,-60.59 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        All 4 attachments are included.

GCN Circular #19988
P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team:
Using promptly downlinked XRT event data for GRB 161004B, we find an enhanced XRT position of the afterglow: RA, Dec: 112.1514, -39.8976 which is equivalent to:
```
   RA (J2000)  = 07 28 36.34
   Dec (J2000) = -39 53 51.5
```
with an uncertainty of 2.0 arcseconds (radius, 90% confidence). Analysis of the promptly available data is online at http://www.swift.ac.uk/sper/715246.
Position enhancement is is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177).
This circular is an official product of the Swift-XRT team.
GCN Circular #19991
P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team.
Using 3535 s of XRT Photon Counting mode data and 5 UVOT images for GRB 161004B, we find an astrometrically corrected X-ray position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 112.15126, -39.89791 which is equivalent to:
```
RA (J2000): 07h 28m 36.30s
Dec (J2000): -39d 53' 52.5"
```
with an uncertainty of 1.4 arcsec (radius, 90% confidence).
This position may be improved as more data are received. The latest position can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177).
This circular was automatically generated, and is an official product of the Swift-XRT team.
GCN Circular #19994
V. D'Elia (ASDC), D.N. Burrows (PSU), T.G.R. Roegiers (PSU), L.M. McCauley (PSU), P.A. Evans (U. Leicester), S.L. Gibson (U. Leicester), J.P. Osborne (U. Leicester), A. Melandri (INAF-OAB) and A. D'Ai report on behalf of the Swift-XRT team:
We have analysed 7.1 ks of XRT data for GRB 161004B (D'Ai et al. GCN Circ. 19987), from 63 s to 28.2 ks after the BAT trigger. The data comprise 77 s in Windowed Timing (WT) mode (the first 9 s were taken while Swift was slewing) with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Evans et al. (GCN Circ. 19988).
The light curve can be modelled with an initial power-law decay with an index of alpha=0.89 (+/-0.05), followed by a break at T+2716 s to an alpha of 1.44 (+0.30, -0.22).
A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 1.99 (+0.19, -0.18). The best-fitting absorption column is 1.14 (+0.21, -0.19) x 10^22 cm^-2, in excess of the Galactic value of 3.5 x 10^21 cm^-2 (Willingale et al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 5.1 x 10^-11 (9.7 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     1.14 (+0.21, -0.19) x 10^22 cm^-2
Galactic foreground: 3.5 x 10^21 cm^-2
Excess significance: 7.1 sigma
Photon index:	     1.99 (+0.19, -0.18)
```
If the light curve continues to decay with a power-law decay index of 1.44, the count rate at T+24 hours will be 2.1 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.1 x 10^-13 (2.0 x 10^-13) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00715246.
This circular is an official product of the Swift-XRT team.
GCN Circular #19995
T. Sakamoto (AGU), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC), A. D'Ai (INAF-IASFPA), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):
Using the data set from T-60 to T+243 sec from the recent telemetry downlink, we report further analysis of BAT GRB 161004B (trigger #715246) (D'Ai, et al., GCN Circ. 19987). The BAT ground-calculated position is RA, Dec = 112.156, -39.896 deg which is
```
    RA(J2000)  =  07h 28m 37.4s
    Dec(J2000) = -39d 53' 47.3"
```
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 75%.
The mask-weighted light curve shows two overlapping peaks starting at T-10 sec, peaking at T+1 sec and ending at T+40 sec. T90 (15-350 keV) is 15.9 +- 0.7 sec (estimated error including systematics).
The time-averaged spectrum from T-5.16 to T+27.31 sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 1.21 +- 0.13, and Epeak of 177 +- 73 keV (chi squared 35.21 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 8.8 +- 0.2 x 10^-6 erg/cm2 and the 1-sec peak flux measured from T+0.36 sec in the 15-150 keV band is 10.1 +- 0.4 ph/cm2/sec. A fit to a simple power law gives a photon index of 1.47 +- 0.03 (chi squared 47.75 for 57 d.o.f.). All the quoted errors are at the 90% confidence level.
The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/715246/BA/
GCN Circular #19996
V. Kumar, V. Sharma, D. Bhattacharya and V. Bhalerao (IUCAA), A. R. Rao (TIFR) and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:
Analysis of AstroSat CZTI data showed clear detection of GRB161004B (Swift BAT detection: D.Palmer et al., GCN Circ. 19987) in the 40-200 keV energy range. The light curve shows a single peak at 23:07:59.0 UT, coincident with the Swift Trigger. The measured peak count rate is 187.3 counts/sec above the background in combined data of four quadrants, with a total of 1393.0 counts. The local mean background count rate was 313.7 counts/sec. Using cumulative rates, we measure a T90 of 13.1 secs.
CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.
GCN Circular #19997
F. E. Marshall (NASA/GSFC) and A. D'Ai (INAF-IASFPA) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 161004B 82 s after the BAT trigger (D'Ai et al., GCN Circ. 19987). No optical afterglow consistent with the XRT position (Evans et al., GCN Circ. 19991) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent exposures are:
```
Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC            82          232          147         >20.8
u_FC               294          544          246         >19.6
white               82         1886          431         >21.2
v                  624         1937          156         >19.5
b                  550         1862          136         >19.6
u                  294         1836          363         >19.6
w1                 674         1812          136         >18.9
m2                5622         5747          123         >18.8
w2                 600         1736          136         >18.7
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.54 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #19998
R. Hamburg (UAH) and C. Meegan (UAH) report on behalf of the Fermi GBM Team:
"At 23:07:54.79 UT on 04 October 2016, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 161004B (trigger 497315278 / 161004964) which was also detected by the Swift BAT (D'Ai et al. 2016, GCN 19987) The GBM on-ground location is consistent with the Swift position.
The trigger resulted in an Autonomous Repoint Request (ARR) by the GBM Flight Software owing to the high peak flux of the GRB. This ARR was accepted and the spacecraft slewed to the GBM in-flight location. The initial angle from the Fermi LAT boresight to the Swift location is 69 degrees.
The GBM light curve consists of a single peak with a duration (T90) of about 14 s (50-300 keV). The time-averaged spectrum from T0-0.0 s to T0+18.4 s is best fit by a Band function with Epeak = 132 +/- 6 keV, alpha = -0.75 +/- 0.04, and beta = -2.4 +/- 0.1.
The event fluence (10-1000 keV) in this time interval is (1.877 +/- 0.039)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+4.7 s in the 10-1000 keV band is 15.4 +/- 0.4 ph/s/cm^2.
The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN Circular #20003
Y. Yamada, A. Yoshida, T. Sakamoto, Y. Kawakubo, M. Moriyama (AGU), K. Yamaoka (Nagoya U), S. Nakahira (JAXA), I. Takahashi (IPMU), Y. Asaoka, S. Ozawa, S. Torii (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U), W. Ishizaki (ICRR), M. L. Cherry (LSU), S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena) and the CALET collaboration:
The long-duration GRB 161004B (D'Ai et al., GCN Circ. 19987; Kumar et al., GCN Circ. 19996; Hamburg et al., GCN Circ. 19998; INTEGRAL-SPI/ACS trigger #7590) triggered the CALET Gamma-ray Burst Monitor (CGBM) at 23:07:52.64 on 4 October 2016. The burst signal was seen by the SGM instrument.
The light curve of the SGM shows a single peak starting at T0, peaking at T+7 sec and ending at T+15 sec. The T90 duration measured by the SGM data is 11.1 +- 0.9 sec (40-450 keV).
The light curve is available at
http://cgbm.calet.jp/cgbm_trigger/flight/1159657616/
The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at the Waseda University.
GCN Circular #20005
A. Tsvetkova, S. Golenetskii, R.Aptekar, D. Frederiks, P. Oleynik, M. Ulanov, D. Svinkin, A. Lysenko, A. Kozlova and T. Cline on behalf of the Konus-Wind team, report:
The long-duration GRB 161004B (Swift-BAT trigger #715246: D'Ai et al., GCN 19987; Sakamoto et al., GCN 19995; Fermi GBM detection: Hamburg & Meegan, GCN 19998; CALET Gamma-Ray Burst Monitor detection: Yamada et al., GCN 20003) triggered Konus-Wind at T0=83274.317 s UT (23:07:54.317).
The burst light curve shows a single pulse with a total duration of ~18 s. The emission is seen up to ~2 MeV.
As observed by Konus-Wind, the burst had a fluence of 1.71(-0.07,+0.08)x10^-5 erg/cm2, and a 64-ms peak energy flux, measured from T0+4.144 s, of 3.43(-0.80,+0.80)x10^-6 erg/cm2/s (both in the 20 keV - 10 MeV energy range).
The time-integrated spectrum of the burst (measured from T0 to T0+15.616 s) is best fit in the 20 keV - 2 MeV range by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) with alpha = -1.05(-0.09,+0.09), and Ep = 175(-12,+14) keV (chi2 = 56/58 dof). Fitting by the GRB (Band) model yields the same alpha and Ep, and an upper limit on the high energy photon index: beta < -3.14 (chi2 = 56/57 dof).
The spectrum near the peak count rate (measured from T0 to T0+7.424 s) is best fit in the 20 keV - 2 MeV range by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) with alpha = -0.71(-0.10,+0.11), and Ep = 210(-13,+15) keV (chi2 = 67/58 dof). Fitting by the GRB (Band) model yields the same alpha and Ep, and an upper limit on the high energy photon index: beta < -3.12 (chi2 = 67/57 dof).
The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB161004_T83274/
All the quoted errors are at the 90% confidence level. All the quoted values are preliminary.

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Jochen Greiner, last update: 06-Oct-2016 [Disclaimer]