Gamma-ray Burst 151006A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 06 Oct 15 09:55:20 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     657750,   Seg_Num: 0
GRB_RA:          147.451d {+09h 49m 48s} (J2000),
                 147.786d {+09h 51m 09s} (current),
                 146.379d {+09h 45m 31s} (1950)
GRB_DEC:         +70.509d {+70d 30' 31"} (J2000),
                 +70.434d {+70d 26' 04"} (current),
                 +70.742d {+70d 44' 31"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       5122 [cnts]    Image_Peak=543 [image_cnts]
TRIGGER_DUR:     1.024 [sec] 
TRIGGER_INDEX:   146     E_range: 25-100 keV
BKG_INTEN:       20070 [cnts]
BKG_TIME:        35688.76 SOD {09:54:48.76} UT
BKG_DUR:         8 [sec]
GRB_DATE:        17301 TJD;   279 DOY;   15/10/06
GRB_TIME:        35701.88 SOD {09:55:01.88} UT
GRB_PHI:         119.13 [deg]
GRB_THETA:         1.54 [deg]
SOLN_STATUS:     0x20000003
RATE_SIGNIF:     47.19 [sigma]
IMAGE_SIGNIF:    16.58 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +2  +5  +0  +0 -15  +0 
SUN_POSTN:       191.81d {+12h 47m 13s}   -5.07d {-05d 04' 02"}
SUN_DIST:         80.99 [deg]   Sun_angle= 2.9 [hr] (West of Sun)
MOON_POSTN:      122.02d {+08h 08m 04s}  +15.42d {+15d 24' 54"}
MOON_DIST:        57.23 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      140.91, 39.67 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      117.53, 52.51 [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 = 40.90,18.18 [deg].  
COMMENTS:           
COMMENTS:        NOTE: This BAT event is temporally(4.0<100sec) coincident with the FERMI_GBM event (trignum=465818101).

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Tue 06 Oct 15 09:55:26 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      46
TRIGGER_NUM:     465818101
GRB_RA:          191.183d {+12h 44m 44s} (J2000),
                 191.343d {+12h 45m 22s} (current),
                 190.673d {+12h 42m 42s} (1950)
GRB_DEC:         +67.867d {+67d 52' 00"} (J2000),
                 +67.781d {+67d 46' 50"} (current),
                 +68.140d {+68d 08' 24"} (1950)
GRB_ERROR:       14.55 [deg radius, statistical plus systematic]
GRB_INTEN:       126 [cnts/sec]
DATA_SIGNIF:     9.10 [sigma]
INTEG_TIME:      2.048 [sec]
GRB_DATE:        17301 TJD;   279 DOY;   15/10/06
GRB_TIME:        35697.83 SOD {09:54:57.83} UT
GRB_PHI:          15.98 [deg]
GRB_THETA:        40.00 [deg]
DATA_TIME_SCALE: 2.0480 [sec]
HARD_RATIO:      0.54
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      91%  GRB
2nd_MOST_LIKELY:   4%  Generic Transient
DETECTORS:       1,1,0, 1,0,0, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:       191.81d {+12h 47m 13s}   -5.07d {-05d 04' 02"}
SUN_DIST:         72.85 [deg]   Sun_angle= 0.0 [hr] (West of Sun)
MOON_POSTN:      122.02d {+08h 08m 05s}  +15.41d {+15d 24' 54"}
MOON_DIST:        67.99 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      123.90, 49.25 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      140.80, 61.51 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2015/bn151006413/quicklook/glg_lc_medres34_bn151006413.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 212.95,23.00 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(4.0<100sec) coincident with the SWIFT_BAT event (trignum=657750).

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Tue 06 Oct 15 09:55:35 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      57
TRIGGER_NUM:     465818101
GRB_RA:          152.450d {+10h 09m 48s} (J2000),
                 152.780d {+10h 11m 07s} (current),
                 151.391d {+10h 05m 34s} (1950)
GRB_DEC:         +72.483d {+72d 28' 60"} (J2000),
                 +72.405d {+72d 24' 19"} (current),
                 +72.729d {+72d 43' 44"} (1950)
GRB_ERROR:       6.92 [deg radius, statistical plus systematic]
GRB_INTEN:       257 [cnts/sec]
DATA_SIGNIF:     25.40 [sigma]
INTEG_TIME:      4.096 [sec]
GRB_DATE:        17301 TJD;   279 DOY;   15/10/06
GRB_TIME:        35697.83 SOD {09:54:57.83} UT
GRB_PHI:           0.00 [deg]
GRB_THETA:        30.00 [deg]
DATA_TIME_SCALE: 4.0960 [sec]
HARD_RATIO:      0.77
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      96%  GRB
2nd_MOST_LIKELY:   2%  Generic Transient
DETECTORS:       1,1,0, 1,0,0, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:       191.81d {+12h 47m 13s}   -5.07d {-05d 04' 02"}
SUN_DIST:         81.39 [deg]   Sun_angle= 2.6 [hr] (West of Sun)
MOON_POSTN:      122.02d {+08h 08m 05s}  +15.41d {+15d 24' 53"}
MOON_DIST:        59.75 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      137.62, 39.70 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      117.76, 55.04 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2015/bn151006413/quicklook/glg_lc_medres34_bn151006413.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 212.95,23.00 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(4.0<100sec) coincident with the SWIFT_BAT event (trignum=657750).

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Tue 06 Oct 15 09:55:52 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      56
TRIGGER_NUM:     465818101
GRB_RA:          160.970d {+10h 43m 53s} (J2000),
                 161.273d {+10h 45m 06s} (current),
                 159.993d {+10h 39m 58s} (1950)
GRB_DEC:         +74.410d {+74d 24' 36"} (J2000),
                 +74.327d {+74d 19' 37"} (current),
                 +74.672d {+74d 40' 21"} (1950)
GRB_ERROR:       4.86 [deg radius, statistical only]
DATA_SIGNIF:     19.30 [sigma]
DATA_INTERVAL:   4.096 [sec]
GRB_DATE:        17301 TJD;   279 DOY;   15/10/06
GRB_TIME:        35697.83 SOD {09:54:57.83} UT
GRB_PHI:           6.00 [deg]
GRB_THETA:        30.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4153 (Gnd S/W Version number)
SUN_POSTN:       191.81d {+12h 47m 13s}   -5.07d {-05d 04' 03"}
SUN_DIST:         81.56 [deg]   Sun_angle= 2.0 [hr] (West of Sun)
MOON_POSTN:      122.02d {+08h 08m 06s}  +15.41d {+15d 24' 51"}
MOON_DIST:        62.77 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      133.61, 39.96 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      118.73, 58.09 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2015/bn151006413/quicklook/glg_lc_medres34_bn151006413.gif
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        In the LAT Field-of-view.  
COMMENTS:        Bright hard burst in the GBM.  
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:           
COMMENTS:        NOTE: This GBM event is temporally(4.0<100sec) coincident with the SWIFT_BAT event (trignum=657750).

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Tue 06 Oct 15 09:56:54 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      2
TRIGGER_NUM:     465818101
GRB_RA:          145.610d {+09h 42m 26s} (J2000),
                 145.963d {+09h 43m 51s} (current),
                 144.476d {+09h 37m 54s} (1950)
GRB_DEC:         +71.990d {+71d 59' 24"} (J2000),
                 +71.917d {+71d 55' 03"} (current),
                 +72.218d {+72d 13' 05"} (1950)
GRB_ERROR:       2.62 [deg radius, statistical only]
DATA_SIGNIF:     35.90 [sigma]
DATA_INTERVAL:   10.240 [sec]
GRB_DATE:        17301 TJD;   279 DOY;   15/10/06
GRB_TIME:        35697.83 SOD {09:54:57.83} UT
GRB_PHI:         356.00 [deg]
GRB_THETA:        29.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   41531 (Gnd S/W Version number)
SUN_POSTN:       191.81d {+12h 47m 13s}   -5.07d {-05d 04' 04"}
SUN_DIST:         82.45 [deg]   Sun_angle= 3.1 [hr] (West of Sun)
MOON_POSTN:      122.03d {+08h 08m 08s}  +15.41d {+15d 24' 46"}
MOON_DIST:        58.25 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      139.76, 38.35 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      115.35, 53.42 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2015/bn151006413/quicklook/glg_lc_medres34_bn151006413.gif
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        In the LAT Field-of-view.  
COMMENTS:        This is likely a Long GRB.  
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:           
COMMENTS:        NOTE: This GBM event is temporally(2.0<100sec) coincident with the INTEGRAL_SPIACS event (trignum=7263).

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Tue 06 Oct 15 09:57:13 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      3
TRIGGER_NUM:     465818101
GRB_RA:          147.440d {+09h 49m 46s} (J2000),
                 147.779d {+09h 51m 07s} (current),
                 146.351d {+09h 45m 24s} (1950)
GRB_DEC:         +71.140d {+71d 08' 24"} (J2000),
                 +71.066d {+71d 03' 57"} (current),
                 +71.373d {+71d 22' 24"} (1950)
GRB_ERROR:       2.53 [deg radius, statistical only]
DATA_SIGNIF:     43.60 [sigma]
DATA_INTERVAL:   16.384 [sec]
GRB_DATE:        17301 TJD;   279 DOY;   15/10/06
GRB_TIME:        35697.83 SOD {09:54:57.83} UT
GRB_PHI:         356.00 [deg]
GRB_THETA:        30.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   41531 (Gnd S/W Version number)
SUN_POSTN:       191.81d {+12h 47m 14s}   -5.07d {-05d 04' 04"}
SUN_DIST:         81.44 [deg]   Sun_angle= 2.9 [hr] (West of Sun)
MOON_POSTN:      122.04d {+08h 08m 08s}  +15.41d {+15d 24' 44"}
MOON_DIST:        57.78 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      140.24, 39.30 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      116.94, 53.04 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2015/bn151006413/quicklook/glg_lc_medres34_bn151006413.gif
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        In the LAT Field-of-view.  
COMMENTS:        This is likely a Long GRB.  
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:           
COMMENTS:        NOTE: This GBM event is temporally(2.0<100sec) coincident with the INTEGRAL_SPIACS event (trignum=7263).

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Tue 06 Oct 15 09:58:36 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      4
TRIGGER_NUM:     465818101
GRB_RA:          147.210d {+09h 48m 50s} (J2000),
                 147.550d {+09h 50m 12s} (current),
                 146.120d {+09h 44m 29s} (1950)
GRB_DEC:         +71.070d {+71d 04' 12"} (J2000),
                 +70.996d {+70d 59' 46"} (current),
                 +71.303d {+71d 18' 09"} (1950)
GRB_ERROR:       2.26 [deg radius, statistical only]
DATA_SIGNIF:     45.70 [sigma]
DATA_INTERVAL:   21.504 [sec]
GRB_DATE:        17301 TJD;   279 DOY;   15/10/06
GRB_TIME:        35697.83 SOD {09:54:57.83} UT
GRB_PHI:         356.00 [deg]
GRB_THETA:        30.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   41531 (Gnd S/W Version number)
SUN_POSTN:       191.81d {+12h 47m 14s}   -5.07d {-05d 04' 05"}
SUN_DIST:         81.44 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:      122.05d {+08h 08m 11s}  +15.41d {+15d 24' 37"}
MOON_DIST:        57.68 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      140.37, 39.28 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      116.90, 52.94 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2015/bn151006413/quicklook/glg_lc_medres34_bn151006413.gif
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        In the LAT Field-of-view.  
COMMENTS:        This is likely a Long GRB.  
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:           
COMMENTS:        NOTE: This GBM event is temporally(2.0<100sec) coincident with the INTEGRAL_SPIACS event (trignum=7263).

GCN NOTICE

 
TITLE:          GCN/INTEGRAL NOTICE
NOTICE_DATE:    Tue 06 Oct 15 09:56:20 UT
NOTICE_TYPE:    INTEGRAL SPI ACS Trigger
TRIGGER_NUM:    7263,   Sub_Num: 0
GRB_INTEN:      9.22 [sigma]   
GRB_TIME:       35695.46 SOD {09:54:55.46} UT
GRB_DATE:       17301 TJD;   279 DOY;   15/10/06
COMMENTS:       INTEGRAL SPI_ACS GRB Trigger.
COMMENTS:       Time_Scale=2.0000 and Time_Error=1.0000.
COMMENTS:
COMMENTS:       NOTE: This SPIACS event is temporally(2.0<100sec) coincident with the FERMI_GBM event (trignum=465818101).
COMMENTS:
COMMENTS:       The SPIACS lightcurve can be found at:
COMMENTS:
ftp://isdcarc.unige.ch/arc/FTP/ibas/spiacs/2015-10/2015-10-06T09-54-55.3257-23335-31632-0.lc

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 06 Oct 15 09:56:28 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     657750,   Seg_Num: 0
GRB_RA:          147.4256d {+09h 49m 42.14s} (J2000),
                 147.7601d {+09h 51m 02.42s} (current),
                 146.3528d {+09h 45m 24.66s} (1950)
GRB_DEC:         +70.5036d {+70d 30' 12.9"} (J2000),
                 +70.4295d {+70d 25' 46.2"} (current),
                 +70.7368d {+70d 44' 12.5"} (1950)
GRB_ERROR:       4.8 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       4.46e-09 [erg/cm2/sec]
GRB_SIGNIF:      11.22 [sigma]
IMG_START_DATE:  17301 TJD;   279 DOY;   15/10/06
IMG_START_TIME:  35750.45 SOD {09:55:50.45} UT,   48.6 [sec] since BAT Trigger Time
TAM[0-3]:        327.62 237.16 261.56 243.12
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       191.81d {+12h 47m 13s}   -5.07d {-05d 04' 03"}
SUN_DIST:         80.99 [deg]   Sun_angle= 2.9 [hr] (West of Sun)
MOON_POSTN:      122.03d {+08h 08m 07s}  +15.41d {+15d 24' 48"}
MOON_DIST:        57.23 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      140.92, 39.66 [deg] galactic lon,lat of the burst
ECL_COORDS:      117.52, 52.50 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 0.59 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 06 Oct 15 09:56:45 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     657750,   Seg_Num: 0
GRB_RA:          147.4256d {+09h 49m 42.1s} (J2000),
                 147.7601d {+09h 51m 02.4s} (current),
                 146.3528d {+09h 45m 24.6s} (1950)
GRB_DEC:         +70.5036d {+70d 30' 12.9"} (J2000),
                 +70.4295d {+70d 25' 46.2"} (current),
                 +70.7368d {+70d 44' 12.5"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       126 [cnts]
IMG_START_DATE:  17301 TJD;   279 DOY;   15/10/06
IMG_START_TIME:  35750.45 SOD {09:55:50.45} UT,   48.6 [sec] since BAT Trigger Time
CENTROID_X:      310.33,  raw= 310  [pixels]
CENTROID_Y:      278.49,  raw= 278  [pixels]
ROLL:            135.21 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -45.50
GRB_POS_XRT_Z:   11.87
IMAGE_URL:       sw00657750000msxps_rw.img
SUN_POSTN:       191.81d {+12h 47m 13s}   -5.07d {-05d 04' 04"}
SUN_DIST:         80.99 [deg]   Sun_angle= 2.9 [hr] (West of Sun)
MOON_POSTN:      122.03d {+08h 08m 07s}  +15.41d {+15d 24' 47"}
MOON_DIST:        57.23 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      140.92, 39.66 [deg] galactic lon,lat of the burst
ECL_COORDS:      117.52, 52.50 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 06 Oct 15 09:56:38 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     657750,   Seg_Num: 0
GRB_RA:          147.4256d {+09h 49m 42.1s} (J2000),
                 147.7601d {+09h 51m 02.4s} (current),
                 146.3528d {+09h 45m 24.6s} (1950)
GRB_DEC:         +70.5036d {+70d 30' 12.9"} (J2000),
                 +70.4295d {+70d 25' 46.2"} (current),
                 +70.7368d {+70d 44' 12.5"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       126 [cnts]
IMG_START_DATE:  17301 TJD;   279 DOY;   15/10/06
IMG_START_TIME:  35750.45 SOD {09:55:50.45} UT,   48.6 [sec] since BAT Trigger Time
CENTROID_X:      310.33,  raw= 310  [pixels]
CENTROID_Y:      278.49,  raw= 278  [pixels]
ROLL:            135.21 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -45.50
GRB_POS_XRT_Z:   11.87
IMAGE_URL:       sw00657750000msxps_rw.img
SUN_POSTN:       191.81d {+12h 47m 13s}   -5.07d {-05d 04' 03"}
SUN_DIST:         80.99 [deg]   Sun_angle= 2.9 [hr] (West of Sun)
MOON_POSTN:      122.03d {+08h 08m 07s}  +15.41d {+15d 24' 47"}
MOON_DIST:        57.23 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      140.92, 39.66 [deg] galactic lon,lat of the burst
ECL_COORDS:      117.52, 52.50 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 06 Oct 15 09:58:49 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     657750,   Seg_Num: 0
GRB_RA:          147.451d {+09h 49m 48s} (J2000),
                 147.786d {+09h 51m 09s} (current),
                 146.379d {+09h 45m 31s} (1950)
GRB_DEC:         +70.509d {+70d 30' 31"} (J2000),
                 +70.434d {+70d 26' 04"} (current),
                 +70.742d {+70d 44' 31"} (1950)
GRB_DATE:        17301 TJD;   279 DOY;   15/10/06
GRB_TIME:        35701.88 SOD {09:55:01.88} UT
TRIGGER_INDEX:   146
GRB_PHI:         119.13 [deg]
GRB_THETA:         1.54 [deg]
DELTA_TIME:      -31.00 [sec]
TRIGGER_DUR:     1.024 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     47.19 [sigma]
IMAGE_SIGNIF:    16.58 [sigma]
LC_URL:          sw00657750000msb.lc
SUN_POSTN:       191.81d {+12h 47m 14s}   -5.07d {-05d 04' 06"}
SUN_DIST:         80.99 [deg]   Sun_angle= 2.9 [hr] (West of Sun)
MOON_POSTN:      122.05d {+08h 08m 12s}  +15.41d {+15d 24' 36"}
MOON_DIST:        57.23 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      140.91, 39.67 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      117.53, 52.51 [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 = 40.90,18.18 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 06 Oct 15 09:59:35 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     657750,   Seg_Num: 0
POINT_RA:        147.460d {+09h 49m 50s} (J2000)
POINT_DEC:       +70.510d {+70d 30' 36"} (J2000)
POINT_ROLL:      135.208d
IMG_START_DATE:  17301 TJD;   279 DOY;   15/10/06
IMG_START_TIME:  35760.03 SOD {09:56:00.03} UT,   58.2 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        4.917
N_STARS:         15
X_OFFSET:        480 [pixels]
Y_OFFSET:        576 [pixels]
X_MAX:           1439 [pixels]
Y_MAX:           1535 [pixels]
DET_THRESH:      19
PHOTO_THRESH:    11
SL_URL:          sw00657750000msufc0058.fits
SUN_POSTN:       191.81d {+12h 47m 14s}   -5.07d {-05d 04' 06"}
SUN_DIST:         80.99 [deg]   Sun_angle= 2.9 [hr] (West of Sun)
MOON_POSTN:      122.06d {+08h 08m 13s}  +15.41d {+15d 24' 32"}
MOON_DIST:        57.24 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      140.91, 39.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      117.53, 52.52 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 06 Oct 15 10:00:06 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     657750,   Seg_Num: 0
POINT_RA:        147.460d {+09h 49m 50s} (J2000)
POINT_DEC:       +70.510d {+70d 30' 36"} (J2000)
POINT_ROLL:      135.208d
IMG_START_DATE:  17301 TJD;   279 DOY;   15/10/06
IMG_START_TIME:  35760.03 SOD {09:56:00.03} UT,   58.2 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        4.917
N_STARS:         15
X_OFFSET:        480 [pixels]
Y_OFFSET:        576 [pixels]
X_MAX:           1439 [pixels]
Y_MAX:           1535 [pixels]
DET_THRESH:      19
PHOTO_THRESH:    11
SL_URL:          sw00657750000msufc0058.fits
SUN_POSTN:       191.81d {+12h 47m 14s}   -5.07d {-05d 04' 07"}
SUN_DIST:         80.99 [deg]   Sun_angle= 2.9 [hr] (West of Sun)
MOON_POSTN:      122.06d {+08h 08m 15s}  +15.41d {+15d 24' 30"}
MOON_DIST:        57.24 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      140.91, 39.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      117.53, 52.52 [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 06 Oct 15 10:01:46 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     657750,   Seg_Num: 0
POINT_RA:        147.460d {+09h 49m 50s} (J2000)
POINT_DEC:       +70.510d {+70d 30' 36"} (J2000)
ROLL:            135.208d
IMG_START_DATE:  17301 TJD;   279 DOY;   15/10/06
IMG_START_TIME:  35760.03 SOD {09:56:00.03} UT,   58.2 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     465818175
X_OFFSET:        816 [pixels]
Y_OFFSET:        964 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       976
Y_GRB_POS:       1124
BINNING_INDEX:   1
IM_URL:          sw00657750000msuni0074.fits
SUN_POSTN:       191.81d {+12h 47m 14s}   -5.07d {-05d 04' 08"}
SUN_DIST:         80.99 [deg]   Sun_angle= 2.9 [hr] (West of Sun)
MOON_POSTN:      122.08d {+08h 08m 18s}  +15.41d {+15d 24' 21"}
MOON_DIST:        57.24 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      140.91, 39.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      117.53, 52.52 [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 06 Oct 15 10:01:56 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     657750,   Seg_Num: 0
POINT_RA:        147.460d {+09h 49m 50s} (J2000)
POINT_DEC:       +70.510d {+70d 30' 36"} (J2000)
ROLL:            135.208d
IMG_START_DATE:  17301 TJD;   279 DOY;   15/10/06
IMG_START_TIME:  35760.03 SOD {09:56:00.03} UT,   58.2 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     465818175
X_OFFSET:        816 [pixels]
Y_OFFSET:        964 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       976
Y_GRB_POS:       1124
BINNING_INDEX:   1
IM_URL:          sw00657750000msuni0074.fits
SUN_POSTN:       191.81d {+12h 47m 14s}   -5.07d {-05d 04' 08"}
SUN_DIST:         80.99 [deg]   Sun_angle= 2.9 [hr] (West of Sun)
MOON_POSTN:      122.08d {+08h 08m 18s}  +15.41d {+15d 24' 20"}
MOON_DIST:        57.24 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      140.91, 39.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      117.53, 52.52 [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 06 Oct 15 10:05:59 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     657750,   Seg_Num: 0
POINT_RA:        147.459d {+09h 49m 50s} (J2000)
POINT_DEC:       +70.510d {+70d 30' 35"} (J2000)
POINT_ROLL:      135.204d
IMG_START_DATE:  17301 TJD;   279 DOY;   15/10/06
IMG_START_TIME:  35972.92 SOD {09:59:32.92} UT,   271.0 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.665
N_STARS:         5
X_OFFSET:        496 [pixels]
Y_OFFSET:        644 [pixels]
X_MAX:           1455 [pixels]
Y_MAX:           1603 [pixels]
DET_THRESH:      11
PHOTO_THRESH:    5
SL_URL:          sw00657750000msufc0271.fits
SUN_POSTN:       191.81d {+12h 47m 15s}   -5.07d {-05d 04' 12"}
SUN_DIST:         80.99 [deg]   Sun_angle= 2.9 [hr] (West of Sun)
MOON_POSTN:      122.11d {+08h 08m 27s}  +15.40d {+15d 23' 59"}
MOON_DIST:        57.24 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      140.91, 39.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      117.53, 52.52 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 06 Oct 15 10:06:16 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     657750,   Seg_Num: 0
POINT_RA:        147.459d {+09h 49m 50s} (J2000)
POINT_DEC:       +70.510d {+70d 30' 35"} (J2000)
POINT_ROLL:      135.204d
IMG_START_DATE:  17301 TJD;   279 DOY;   15/10/06
IMG_START_TIME:  35972.92 SOD {09:59:32.92} UT,   271.0 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.665
N_STARS:         5
X_OFFSET:        496 [pixels]
Y_OFFSET:        644 [pixels]
X_MAX:           1455 [pixels]
Y_MAX:           1603 [pixels]
DET_THRESH:      11
PHOTO_THRESH:    5
SL_URL:          sw00657750000msufc0271.fits
SUN_POSTN:       191.81d {+12h 47m 15s}   -5.07d {-05d 04' 13"}
SUN_DIST:         80.99 [deg]   Sun_angle= 2.9 [hr] (West of Sun)
MOON_POSTN:      122.11d {+08h 08m 28s}  +15.40d {+15d 23' 58"}
MOON_DIST:        57.24 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      140.91, 39.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      117.53, 52.52 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        If you have elected to receive attachments:  
COMMENTS:        The uvot_catalog_srclist.fits.gz file does not exist; skipping the attachment.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 06 Oct 15 10:07:21 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     657750,   Seg_Num: 0
POINT_RA:        147.459d {+09h 49m 50s} (J2000)
POINT_DEC:       +70.510d {+70d 30' 35"} (J2000)
ROLL:            135.204d
IMG_START_DATE:  17301 TJD;   279 DOY;   15/10/06
IMG_START_TIME:  35972.92 SOD {09:59:32.92} UT,   271.0 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     465818388
X_OFFSET:        816 [pixels]
Y_OFFSET:        964 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       976
Y_GRB_POS:       1124
BINNING_INDEX:   1
IM_URL:          sw00657750000msuni0287.fits
SUN_POSTN:       191.81d {+12h 47m 15s}   -5.07d {-05d 04' 14"}
SUN_DIST:         80.99 [deg]   Sun_angle= 2.9 [hr] (West of Sun)
MOON_POSTN:      122.12d {+08h 08m 30s}  +15.40d {+15d 23' 52"}
MOON_DIST:        57.24 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      140.91, 39.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      117.53, 52.52 [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 06 Oct 15 10:07:32 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     657750,   Seg_Num: 0
POINT_RA:        147.459d {+09h 49m 50s} (J2000)
POINT_DEC:       +70.510d {+70d 30' 35"} (J2000)
ROLL:            135.204d
IMG_START_DATE:  17301 TJD;   279 DOY;   15/10/06
IMG_START_TIME:  35972.92 SOD {09:59:32.92} UT,   271.0 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     465818388
X_OFFSET:        816 [pixels]
Y_OFFSET:        964 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       976
Y_GRB_POS:       1124
BINNING_INDEX:   1
IM_URL:          sw00657750000msuni0287.fits
SUN_POSTN:       191.81d {+12h 47m 15s}   -5.07d {-05d 04' 14"}
SUN_DIST:         80.99 [deg]   Sun_angle= 2.9 [hr] (West of Sun)
MOON_POSTN:      122.13d {+08h 08m 30s}  +15.40d {+15d 23' 51"}
MOON_DIST:        57.24 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      140.91, 39.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      117.53, 52.52 [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:        If you have elected to receive attachments:  
COMMENTS:        The uvot_catalog_image.fits.gz file does not exist; skipping the attachment.

GCN Circular #18398
D. Kocevski (NASA/GSFC/ORAU), S. D. Barthelmy (GSFC), P. A. Evans (U Leicester), K. L. Page (U Leicester) and B. Sbarufatti (INAF-OAB/PSU) report on behalf of the Swift Team:
At 09:55:01 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 151006A (trigger=657750). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 147.451, +70.509, which is
```
   RA(J2000)  =  09h 49m 48s
   Dec(J2000) = +70d 30' 31"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows a single FRED-like peak structure with a duration of about 40 sec. The peak count rate was ~4000 counts/sec (15-350 keV), at ~0 sec after the trigger.
The XRT began observing the field at 09:55:50.4 UT, 48.6 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 147.4256, 70.5036 which is equivalent to:
```
   RA(J2000)  = +09h 49m 42.14s
   Dec(J2000) = +70d 30' 13.0"
```
with an uncertainty of 4.8 arcseconds (radius, 90% containment). This location is 36 arcseconds from the BAT onboard position, within the BAT error circle. No event data are yet available to determine the column density using X-ray spectroscopy.
UVOT took a finding chart exposure of 150 seconds with the White filter starting 58 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 0.24.
Burst Advocate for this burst is D. Kocevski (dankocevski AT gmail.com). 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 NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 06 Oct 15 10:13:13 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     657750,   Seg_Num: 0
POINT_RA:        147.459d {+09h 49m 50s} (J2000)
POINT_DEC:       +70.510d {+70d 30' 35"} (J2000)
POINT_ROLL:      135.203d
IMG_START_DATE:  17301 TJD;   279 DOY;   15/10/06
IMG_START_TIME:  36575.19 SOD {10:09:35.19} UT,   873.3 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.772
N_STARS:         36
X_OFFSET:        256 [pixels]
Y_OFFSET:        404 [pixels]
X_MAX:           1695 [pixels]
Y_MAX:           1843 [pixels]
DET_THRESH:      16
PHOTO_THRESH:    9
SL_URL:          sw00657750000msufc0873.fits
SUN_POSTN:       191.82d {+12h 47m 16s}   -5.07d {-05d 04' 19"}
SUN_DIST:         80.99 [deg]   Sun_angle= 2.9 [hr] (West of Sun)
MOON_POSTN:      122.18d {+08h 08m 42s}  +15.39d {+15d 23' 22"}
MOON_DIST:        57.24 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      140.91, 39.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      117.53, 52.52 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 06 Oct 15 10:13:24 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     657750,   Seg_Num: 0
POINT_RA:        147.459d {+09h 49m 50s} (J2000)
POINT_DEC:       +70.510d {+70d 30' 35"} (J2000)
POINT_ROLL:      135.203d
IMG_START_DATE:  17301 TJD;   279 DOY;   15/10/06
IMG_START_TIME:  36575.19 SOD {10:09:35.19} UT,   873.3 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.772
N_STARS:         36
X_OFFSET:        256 [pixels]
Y_OFFSET:        404 [pixels]
X_MAX:           1695 [pixels]
Y_MAX:           1843 [pixels]
DET_THRESH:      16
PHOTO_THRESH:    9
SL_URL:          sw00657750000msufc0873.fits
SUN_POSTN:       191.82d {+12h 47m 16s}   -5.07d {-05d 04' 19"}
SUN_DIST:         80.99 [deg]   Sun_angle= 2.9 [hr] (West of Sun)
MOON_POSTN:      122.18d {+08h 08m 43s}  +15.39d {+15d 23' 21"}
MOON_DIST:        57.24 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      140.91, 39.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      117.53, 52.52 [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 06 Oct 15 10:14:10 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     657750,   Seg_Num: 0
GRB_RA:          147.4259d {+09h 49m 42.21s} (J2000),
                 147.7604d {+09h 51m 02.49s} (current),
                 146.3531d {+09h 45m 24.74s} (1950)
GRB_DEC:         +70.5027d {+70d 30' 09.7"} (J2000),
                 +70.4286d {+70d 25' 43.0"} (current),
                 +70.7359d {+70d 44' 09.2"} (1950)
GRB_ERROR:       2.3 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  17301 TJD;   279 DOY;   15/10/06
IMG_START_TIME:  36294.00 SOD {10:04:54.00} UT,   592.1 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       191.82d {+12h 47m 16s}   -5.07d {-05d 04' 20"}
SUN_DIST:         81.00 [deg]   Sun_angle= 2.9 [hr] (West of Sun)
MOON_POSTN:      122.18d {+08h 08m 44s}  +15.39d {+15d 23' 17"}
MOON_DIST:        57.22 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      140.92, 39.66 [deg] galactic lon,lat of the burst
ECL_COORDS:      117.52, 52.50 [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 1.1% < P(seren) < 2.8%.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 06 Oct 15 10:14:39 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     657750,   Seg_Num: 0
POINT_RA:        147.459d {+09h 49m 50s} (J2000)
POINT_DEC:       +70.510d {+70d 30' 35"} (J2000)
ROLL:            135.203d
IMG_START_DATE:  17301 TJD;   279 DOY;   15/10/06
IMG_START_TIME:  36575.19 SOD {10:09:35.19} UT,   873.3 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     465818990
X_OFFSET:        815 [pixels]
Y_OFFSET:        963 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       975
Y_GRB_POS:       1123
BINNING_INDEX:   1
IM_URL:          sw00657750000msuni0889.fits
SUN_POSTN:       191.82d {+12h 47m 16s}   -5.07d {-05d 04' 21"}
SUN_DIST:         80.99 [deg]   Sun_angle= 2.9 [hr] (West of Sun)
MOON_POSTN:      122.19d {+08h 08m 45s}  +15.39d {+15d 23' 14"}
MOON_DIST:        57.24 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      140.91, 39.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      117.53, 52.52 [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 06 Oct 15 10:14:48 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     657750,   Seg_Num: 0
POINT_RA:        147.459d {+09h 49m 50s} (J2000)
POINT_DEC:       +70.510d {+70d 30' 35"} (J2000)
ROLL:            135.203d
IMG_START_DATE:  17301 TJD;   279 DOY;   15/10/06
IMG_START_TIME:  36575.19 SOD {10:09:35.19} UT,   873.3 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     465818990
X_OFFSET:        815 [pixels]
Y_OFFSET:        963 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       975
Y_GRB_POS:       1123
BINNING_INDEX:   1
IM_URL:          sw00657750000msuni0889.fits
SUN_POSTN:       191.82d {+12h 47m 16s}   -5.07d {-05d 04' 21"}
SUN_DIST:         80.99 [deg]   Sun_angle= 2.9 [hr] (West of Sun)
MOON_POSTN:      122.19d {+08h 08m 46s}  +15.39d {+15d 23' 13"}
MOON_DIST:        57.24 [deg]
MOON_ILLUM:      35 [%]
GAL_COORDS:      140.91, 39.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      117.53, 52.52 [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 #18399
P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team:
Using promptly downlinked XRT event data for GRB 151006A, we find an enhanced XRT position of the afterglow: RA, Dec: 147.4260, 70.5027 which is equivalent to:
```
   RA (J2000)  = 09 49 42.25
   Dec (J2000) = +70 30 09.7
```
with an uncertainty of 2.3 arcseconds (radius, 90% confidence). Analysis of the promptly available data is online at http://www.swift.ac.uk/sper/657750.
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 #18400
K. S. Kawabata, R. Itoh, M. Kawabata, T. Nakaoka, H. Mori, K. Takaki (Hiroshima Univ.), and R. Shimotani (Kagawa Univ.) report on behalf of Kanata team:
We performed a series of optical imaging-polarimetry for the optical afterglow of GRB151006A (Kocevski et al., GCN 18398) from 73 sec after the Swift/BAT trigger with HOWPol attached to the 1.5-m Kanata telescope at Higashi-Hiroshima Observatory, Japan.
We could not detect any afterglow within the XRT error circle reported in the GCN 18398. We obtained the following preliminary upper limits in our first image (mid-time 88 sec after the trigger) calibrated with UCAC4:
Rc > 17.7
Further analysis is ongoing.
GCN Circular #18402
D. Kuroda, K. Yanagisawa, Y. Shimizu, H. Toda (OAO, NAOJ), S. Nagayama (NAOJ), M. Yoshida (Hiroshima), K. Ohta (Kyoto) and N. Kawai(Tokyo Tech) report on behalf of MITSuME and OISTER collaboration:
We observed the field of GRB 151006A (Kocevski et al., GCNC 18398) with the optical three color (g', Rc and Ic) CCD camera attached to the MITSuME 50cm telescope of Okayama Astrophysical Observatory.
The observation started on 2015-10-06 09:56:35 UT (~93 sec after the burst). We did not find any new point source within the enhanced XRT error circle (Evans, GCNC 18399) in all the three bands.
Three sigma upper limits of the OT are listed below. We used GSC2.3 catalog for flux calibration.
```
#T0+[day]  MID-UT    T-EXP[sec]   g'     Rc     Ic
-----------------------------------------------------
0.00707    10:05:12     540.0   >18.6  >18.6  >18.0
-----------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]
```
GCN Circular #18403
M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team.
Using 2266 s of XRT Photon Counting mode data and 5 UVOT images for GRB 151006A, 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 = 147.42592, +70.50299 which is equivalent to:
```
RA (J2000): 09h 49m 42.22s
Dec (J2000): +70d 30' 10.8"
```
with an uncertainty of 1.7 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 #18404
O.J. Roberts (UCD) and C.Meegan (UAH) report on behalf of the Fermi GBM Team:
"At 09:54:57.83 UT on 06 October 2015, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 151006A (trigger 465818101/151006413), which was also detected by Swift BAT and XRT (Kocevski et al. 2015, GCN 18398). The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight at the GBM trigger time using the Swift position is 30 degrees.
The GBM light curve consists of a FRED-like peak with a duration (T90) of about 84 s (50-300 keV). The time-averaged spectrum from T0+0 s to T0+83.7 s is best fit by a Band function with Epeak = 227 +/- 53 keV, alpha = -1.17 +/- 0.07, and beta = -1.68 +/- 0.04
The event fluence (10-1000 keV) in this time interval is (1.15 +/- 0.02)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+5.24 s in the 10-1000 keV band is 4.9 +/- 0.2 ph/s/cm^2.
The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN Circular #18405
A. A. Breeveld (UCL-MSSL) and D. Kocevski (NASA/GSFC/ORAU) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 151006A 36 s after the BAT trigger (Kocevski et al., GCN Circ. 18398). No optical afterglow consistent with the XRT position (Goad et al. GCN Circ. 18403) 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            58          208          147         >20.7
u_FC               271          521          246         >19.9
white               58         6351          520         >21.4
v                   36         6754          437         >19.8
b                  527         6146          236         >20.3
u                  271         5941          442         >20.3
w1                5537         5736          197         >19.8
m2                 625         5531          235         >19.7
w2                 577         6557          432         >20.4
```
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).
GCN Circular #18406
M. Ohno (Hiroshima U.), E. Bissaldi (INFN Bari), G. Vianello (Stanford University), D. Kocevski (NASA/GSFC) and F. Longo (University & INFN Trieste) report on behalf of the Fermi-LAT team:
At 09:54:57.83 on October 06, 2015, Fermi-LAT detected high-energy emission from GRB 151006A, which was also detected by Fermi-GBM (trigger 465818101; Roberts et al. GCN 18404) and Swift-BAT (Kocevski et al. GCN 18398).
The GBM location was initially inside the LAT field of view at an angle of ~30 degrees to the LAT boresight. Using the LAT Low Energy (LLE) data selection, over 400 counts above background were detected within a 30 s interval coinciding with the time of the GBM emission. This data selection has insufficient spatial resolution to provide a reliable LAT localization. Processing and analysis of standard data is ongoing.
The Fermi LAT point of contact for this burst is Masanori Ohno (ohno@hep01.hepl.hiroshima-u.ac.jp).
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 #18407
L.M. McCauley (PSU), J.A. Kennea (PSU), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), S.L. Gibson (U. Leicester), V. D'Elia (ASDC), A. D'ai (INAF-IASFPA), A. Maselli (INAF-IASFPA), B. Sbarufatti (INAF-OAB/PSU) and D. Kocevski report on behalf of the Swift-XRT team:
We have analysed 11 ks of XRT data for GRB 151006A (Kocevski et al. GCN Circ. 18398), from 40 s to 29.1 ks after the BAT trigger. The data comprise 552 s in Windowed Timing (WT) mode (the first 7 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 Goad et al. (GCN Circ. 18399).
The light curve can be modelled with an initial power-law decay with an index of alpha=0.3 (+0.7, -1.6), followed by a break at T+64.1 s to an alpha of 1.377 (+0.020, -0.019).
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.45 (+0.06, -0.05). The best-fitting absorption column is 4.9 (+0.5, -0.4) x 10^21 cm^-2, in excess of the Galactic value of 7.7 x 10^20 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 2.08 (+0.17, -0.16) and a best-fitting absorption column of 4.3 (+0.9, -0.8) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.7 x 10^-11 (6.1 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     4.3 (+0.9, -0.8) x 10^21 cm^-2
Galactic foreground: 7.7 x 10^20 cm^-2
Excess significance: 7.1 sigma
Photon index:	     2.08 (+0.17, -0.16)
```
If the light curve continues to decay with a power-law decay index of 1.377, the count rate at T+24 hours will be 4.7 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.7 x 10^-13 (2.9 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/00657750.
This circular is an official product of the Swift-XRT team.
GCN Circular #18408
Kenshi Yanagisawa, Daisuke Kuroda, Yasuhiro Shimizu, Hideyuki Izumiura(OAO/NAOJ), Michitoshi Yoshida (Hiroshima-U), Kouji Ohta(Kyoto-U) and Nobuyuki Kawai(Tokyo Tech.) report on behalf of the MITSuME collaboration:
We observed the field of GRB151006A (Kocevski et al., GCN 18398) in Ks-band with a wide-field near infrared imager at Okayama Astrophysical Observatory (Japan). The imager has effective aperture of 0.91 m.
Observations started from 17:22 UT on 6th October, 7.4h after the BAT trigger, to 18:17 UT. The total exposure of 26.5 min was successfully obtained.
In our co-add image, we did not find any new point source within the enhanced XRT error circle (Goad et al., GCN 18403) down to limiting magnitude of Ks=15.2 (Vega, S/N=10). The photometric calibration was made against 2MASS field stars.
```
T0+[sec]    MID-UT     T-EXP[sec]      Ks
---------------------------------------------------
 +26,819    17:49      1,590           >15.2
---------------------------------------------------
T0+ : Elapsed time after the burt [sec]
T-EXP: Total Exposure time [sec]
```
GCN Circular #18409
J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), N. Gehrels (GSFC), D. Kocevski (NASA/GSFC/ORAU), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):
Using the data set from T-239 to T+800 sec from the recent telemetry downlink, we report further analysis of BAT GRB 151006A (trigger #657750) (Kocevski, et al., GCN Circ. 18398). The BAT ground-calculated position is RA, Dec = 147.426, 70.508 deg which is
```
  RA(J2000)  =  09h 49m 42.3s
  Dec(J2000) = +70d 30' 30.2"
```
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 100%.
The mask-weighted light curve shows a FRED-like structure that starts at ~T-5 s, peaks at ~ T+1 s, and ends at ~ T+310 s. T90 (15-350 keV) is 203.9 +- 41.6 sec (estimated error including systematics).
The time-averaged spectrum from T-4.9 to T+311.2 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.56 +- 0.06. The fluence in the 15-150 keV band is 6.9 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+1.49 sec in the 15-150 keV band is 2.6 +- 0.2 ph/cm2/sec. 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/657750/BA/
GCN Circular #18410
J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), N. Gehrels (GSFC), D. Kocevski (NASA/GSFC/ORAU), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):
Using the data set from T-239 to T+800 sec from the recent telemetry downlink, we report further analysis of BAT GRB 151006A (trigger #657750) (Kocevski, et al., GCN Circ. 18398). The BAT ground-calculated position is RA, Dec = 147.426, 70.508 deg which is
```
  RA(J2000)  =  09h 49m 42.3s
  Dec(J2000) = +70d 30' 30.2"
```
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 100%.
The mask-weighted light curve shows a FRED-like structure that starts at ~T-5 s, peaks at ~ T+1 s, and ends at ~ T+310 s. T90 (15-350 keV) is 203.9 +- 41.6 sec (estimated error including systematics).
The time-averaged spectrum from T-4.9 to T+311.2 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.56 +- 0.06. The fluence in the 15-150 keV band is 6.9 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+1.49 sec in the 15-150 keV band is 2.6 +- 0.2 ph/cm2/sec. 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/657750/BA/
GCN Circular #18411
S. R. Oates (IAA-CSIC), S. Jeong (IAA-CSIC/SKKU), A. Sota, J. C. Tello (IAA-CSIC), A.J. Castro-Tirado (IAA-CSIC/UMA), S. B. Pandey (ARIES Nainital) report on behalf of a larger collaboration:
We observed the field of GRB 151006A (Kocevski et al., GCN Circ. 18398) with the 1.5m OSN telescope at Observatorio de Sierra Nevada (Spain). The observations were carried out in the I band on Oct 7.13159-7.17369 (17.24 - 18.25 hours post bust). We do not detect any new optical source within the enhanced XRT error circle (Goad et al., GCN Circ. 18403) down to a limiting magnitude of I ~21mag.
GCN Circular #18413
S. Golenetskii, R.Aptekar, D. Frederiks, V. Pal'shin, P. Oleynik, M. Ulanov, D. Svinkin, A. Tsvetkova, A. Lysenko, A. Kozlova and T. Cline on behalf of the Konus-Wind team, report:
The long-duration, hard-spectrum GRB 151006A (Swift-BAT trigger #657750: Kocevski et al., GCN 18398; Cummings et al., GCN 18409; Fermi GBM detection: Roberts & Meegan, GCN 18404) triggered Konus-Wind at T0=35697.746 s UT (09:54:57.746).
The burst light curve shows a single FRED-like pulse with a total duration of ~114 s. The emission is seen up to ~10 MeV.
As observed by Konus-Wind, the burst had a fluence of 5.30(-0.87,+0.92)x10^-5 erg/cm2, and a 64-ms peak energy flux, measured from T0+2.928 s, of 5.60(-2.26,+2.23)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+73.984 s) is best fit in the 20 keV - 15 MeV range by the GRB (Band) model with the following parameters: the low-energy photon index alpha = -1.26(-0.23,+0.42), the high energy photon index beta = -1.73(-0.13,+0.09), the peak energy Ep = 223(-132,+514) keV, chi2 = 85/97 dof.
The spectrum near the peak count rate (measured from T0 to T0+8.448 s) is best fit in the 20 keV - 15 MeV range by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) with alpha = -1.40(-0.06,+0.07), and Ep = 2600(-1200,+2900) keV (chi2 = 71/98 dof). Fitting by the GRB (Band) model yields the same alpha and Ep, and an upper limit on the high energy photon index: beta < -1.7 (chi2 = 71/97 dof).
The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB151006_T35697/
All the quoted errors are at the 90% confidence level. All the quoted values are preliminary.
GCN Circular #18415
S.Harita, T.Fujiwara, T. Yoshii, Y. Saito, Y. Tachibana, H. Ohuchi, Y. Yano, S. Kurita, Y.Ono, Y.Muraki, Y. Yatsu, and N. Kawai (Tokyo Tech)
report on behalf of the MITSuME collaboration:
We searched for the optical counterpart of GRB 151006A (D. Kocevski et al. GCN Circular #18398) with the optical three color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm telescope of Akeno Observatory, Yamanashi, Japan.
The observation started on 2015-10-06 15:20:15 UT (~4.4 h after the burst). We did not find any new point source within XRT circle in all three bands.
We obtained following limits for the magnitudes.
```
T0+[sec]      MID-UT      T-EXP[sec]         g'           Rc           Ic
---------------------------------------------------------------------------------------
  19514     17:24:12.2          9240           >21.3      >20.8     > 19.9
---------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time
We used GSC2.3 catalog for flux calibration
```
GCN Circular #18416
E. Mazaeva (IKI), E. Klunko (ISTP), A. Volnova (IKI), I. Korobtsev (ISTP), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration:
We observed the field of Swift GRB 151006A (Kocevski et al., GCN 18398) with AZT-33IK telescope of Sayan observatory (Mondy) starting on Oct. 18 (UT) 16:50:47. We obtained several images in R-filter of 120 s exposure. Within XRT error circle (Goad et al., GCN 18403) we do not detect any optical source. Upper limit is following
```
Date       UT start   t-T0     Filter   Exp.    UL (3 sigma)
                       (mid, days)       (s)

2015-10-06 16:50:47   0.31306  R        35*120  22.4
```
Photometry is based on USNO-B1.0 stars:
```
USNO-B1.0_id R2
1604-0085829 18.23
1604-0085812 16.90
```
GCN Circular #18422
V. Bhalerao (IUCAA), D. Bhattacharya (IUCAA), A. R. Rao (TIFR), S. Vadawale (PRL) report on behalf of the Astrosat CZTI collaboration:
Analysis of Astrosat commissioning data showed the presence of GRB 151006A (Kocevski et al. 2015, GCN 18398) in the Cadmium Zinc Telluride Imager. The source was located 60.7 degrees away from the pointing direction and was detected at energies above 60 keV. Modelling the profile as a fast rise and exponential decay, we measure T90 of 65s, 75s, and 50s in 60-80 keV, 80-100 keV and 100-250 keV bands respectively.
In addition, the GRB is clearly detected in a lightcurve created from double events satisfying Compton scattering criteria (Vadawale et al., 2015, A&A, 578, 73). This demonstrates the feasibility of measuring polarisation for brighter GRBs with CZTI.
GCN Circular #18475
A. Yoshida, T. Sakamoto, I. Takahashi, Y. Kawakubo, K. Senuma, M. Moriyama, Y. Yamada (AGU), K. Yamaoka (Nagoya U), S. Nakahira (JAXA), Y. Asaoka, S. Ozawa, S. Torii (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U), M. L. Cherry (LSU), S. Ricciarini (U of Florence) and the CALET collaboration:
The long-duration GRB 151006A (Kocevski et al., GCN Circ. 18398; Cummings et al., GCN Circ. 18409; Roberts & Meegan, GCN Circ. 18404; Golenetskii et al., GCN Circ. 18413; Bhalerao et al., GCN Circ. 18422) triggered the CALET Gamma-Ray Burst Monitor (CGBM) at 09:54:59.97 UT on 6 October 2015. The clear burst signal was detected by the Soft Gamma-ray Monitor (SGM; 30 keV - 20 MeV) which is a scintillation detector utilized a BGO crystal. Due to a large incident angle of the event, no signal was detected by the Hard X-ray Monitor (HXM; 7 keV - 1 MeV) which is a scintillation detector composed of a LaBr3(Ce) crystal.
The SGM light curve shows two spikes peaking at T0-2s and T0+2s, and the emission ending around T0+~60s. The T90 duration measured by the SGM data is 63 +- 5 s (30 - 1000 keV).
Currently, CALET is in the commissioning phase. Further information about CALET and CGBM can be found at http://calet.jp/en/ and http://www.en.yoshida-agu.net/research/calet-gbm
1608.07388 from 29 Aug 16
A. R. Rao et al.: AstroSat CZT Imager observations of GRB 151006A: timing, spectroscopy, and polarisation study
AstroSat is a multi-wavelength satellite launched on 2015 September 28. The CZT Imager of AstroSat on its very first day of operation detected a long duration gamma-ray burst (GRB) namely GRB 151006A. Using the off-axis imaging and spectral response of the instrument, we demonstrate that CZT Imager can localise this GRB correct to about a few degrees and it can provide, in conjunction with Swift, spectral parameters similar to that obtained from Fermi/GBM. Hence CZT Imager would be a useful addition to the currently operating GRB instruments (Swift and Fermi). Specifically, we argue that the CZT Imager will be most useful for the short hard GRBs by providing localisation for those detected by Fermi and spectral information for those detected only by Swift. We also provide preliminary results on a new exciting capability of this instrument: CZT Imager is able to identify Compton scattered events thereby providing polarisation information for bright GRBs. GRB 151006A, in spite of being relatively faint, shows hints of a polarisation signal at 100-300 keV (though at a low significance level). We point out that CZT Imager should provide significant time resolved polarisation measurements for GRBs that have fluence 3 times higher than that of GRB 151006A. We estimate that the number of such bright GRBs detectable by CZT Imager is 5 - 6 per year. CZT Imager can also act as a good hard X-ray monitoring device for possible electromagnetic counterparts of Gravitational Wave events.

Back to JG's homepage

Jochen Greiner, last update: 29-Aug-2016 [Disclaimer]