Gamma-ray Burst 160826A

(All information courtesy of the instrument teams.)

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Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 26 Aug 16 06:13:38 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     709907,   Seg_Num: 0
GRB_RA:          183.074d {+12h 12m 18s} (J2000),
                 183.300d {+12h 13m 12s} (current),
                 182.401d {+12h 09m 36s} (1950)
GRB_DEC:         -67.689d {-67d 41' 19"} (J2000),
                 -67.781d {-67d 46' 52"} (current),
                 -67.411d {-67d 24' 38"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       32598 [cnts]    Image_Peak=725 [image_cnts]
TRIGGER_DUR:     12.160 [sec] 
TRIGGER_INDEX:   478     E_range: 25-100 keV
BKG_INTEN:       158805 [cnts]
BKG_TIME:        22263.23 SOD {06:11:03.23} UT
BKG_DUR:         64 [sec]
GRB_DATE:        17626 TJD;   239 DOY;   16/08/26
GRB_TIME:        22358.27 SOD {06:12:38.27} UT
GRB_PHI:         -174.52 [deg]
GRB_THETA:         8.00 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     10.44 [sigma]
IMAGE_SIGNIF:    9.26 [sigma]
MERIT_PARAMS:     +1  +0  +0  +4  +2  +0  +0  +1 -16  +0 
SUN_POSTN:       155.37d {+10h 21m 28s}  +10.24d {+10d 14' 30"}
SUN_DIST:         80.55 [deg]   Sun_angle= -1.9 [hr] (East of Sun)
MOON_POSTN:       77.34d {+05h 09m 22s}  +17.62d {+17d 37' 25"}
MOON_DIST:       112.29 [deg]
MOON_ILLUM:      38 [%]
GAL_COORDS:      299.22, -5.10 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      225.57,-57.21 [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 = 166.50,-6.94 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 26 Aug 16 06:14:55 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     709907,   Seg_Num: 0
GRB_RA:          183.1132d {+12h 12m 27.16s} (J2000),
                 183.3393d {+12h 13m 21.42s} (current),
                 182.4401d {+12h 09m 45.62s} (1950)
GRB_DEC:         -67.6636d {-67d 39' 48.9"} (J2000),
                 -67.7562d {-67d 45' 22.1"} (current),
                 -67.3855d {-67d 23' 07.8"} (1950)
GRB_ERROR:       6.2 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       5.77e-10 [erg/cm2/sec]
GRB_SIGNIF:      4.79 [sigma]
IMG_START_DATE:  17626 TJD;   239 DOY;   16/08/26
IMG_START_TIME:  22460.82 SOD {06:14:20.82} UT,   102.5 [sec] since BAT Trigger Time
TAM[0-3]:        327.70 237.21 261.56 243.61
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       155.37d {+10h 21m 28s}  +10.24d {+10d 14' 29"}
SUN_DIST:         80.54 [deg]   Sun_angle= -1.9 [hr] (East of Sun)
MOON_POSTN:       77.35d {+05h 09m 25s}  +17.62d {+17d 37' 29"}
MOON_DIST:       112.31 [deg]
MOON_ILLUM:      38 [%]
GAL_COORDS:      299.23, -5.07 [deg] galactic lon,lat of the burst
ECL_COORDS:      225.55,-57.19 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 1.76 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 26 Aug 16 06:15:05 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     709907,   Seg_Num: 0
GRB_RA:          183.1132d {+12h 12m 27.1s} (J2000),
                 183.3393d {+12h 13m 21.4s} (current),
                 182.4401d {+12h 09m 45.6s} (1950)
GRB_DEC:         -67.6636d {-67d 39' 48.9"} (J2000),
                 -67.7562d {-67d 45' 22.1"} (current),
                 -67.3855d {-67d 23' 07.8"} (1950)
GRB_ERROR:       6.1 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       23 [cnts]
IMG_START_DATE:  17626 TJD;   239 DOY;   16/08/26
IMG_START_TIME:  22460.82 SOD {06:14:20.82} UT,   102.5 [sec] since BAT Trigger Time
CENTROID_X:      281.17,  raw= 281  [pixels]
CENTROID_Y:      262.70,  raw= 263  [pixels]
ROLL:            332.34 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -82.71
GRB_POS_XRT_Z:   -56.87
IMAGE_URL:       sw00709907000msxps_rw.img
SUN_POSTN:       155.37d {+10h 21m 28s}  +10.24d {+10d 14' 29"}
SUN_DIST:         80.54 [deg]   Sun_angle= -1.9 [hr] (East of Sun)
MOON_POSTN:       77.36d {+05h 09m 25s}  +17.62d {+17d 37' 29"}
MOON_DIST:       112.31 [deg]
MOON_ILLUM:      38 [%]
GAL_COORDS:      299.23, -5.07 [deg] galactic lon,lat of the burst
ECL_COORDS:      225.55,-57.19 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 26 Aug 16 06:15:14 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     709907,   Seg_Num: 0
GRB_RA:          183.1132d {+12h 12m 27.1s} (J2000),
                 183.3393d {+12h 13m 21.4s} (current),
                 182.4401d {+12h 09m 45.6s} (1950)
GRB_DEC:         -67.6636d {-67d 39' 48.9"} (J2000),
                 -67.7562d {-67d 45' 22.1"} (current),
                 -67.3855d {-67d 23' 07.8"} (1950)
GRB_ERROR:       6.1 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       23 [cnts]
IMG_START_DATE:  17626 TJD;   239 DOY;   16/08/26
IMG_START_TIME:  22460.82 SOD {06:14:20.82} UT,   102.5 [sec] since BAT Trigger Time
CENTROID_X:      281.17,  raw= 281  [pixels]
CENTROID_Y:      262.70,  raw= 263  [pixels]
ROLL:            332.34 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -82.71
GRB_POS_XRT_Z:   -56.87
IMAGE_URL:       sw00709907000msxps_rw.img
SUN_POSTN:       155.37d {+10h 21m 28s}  +10.24d {+10d 14' 28"}
SUN_DIST:         80.54 [deg]   Sun_angle= -1.9 [hr] (East of Sun)
MOON_POSTN:       77.36d {+05h 09m 26s}  +17.62d {+17d 37' 30"}
MOON_DIST:       112.31 [deg]
MOON_ILLUM:      38 [%]
GAL_COORDS:      299.23, -5.07 [deg] galactic lon,lat of the burst
ECL_COORDS:      225.55,-57.19 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 26 Aug 16 06:16:19 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     709907,   Seg_Num: 0
GRB_RA:          183.074d {+12h 12m 18s} (J2000),
                 183.300d {+12h 13m 12s} (current),
                 182.401d {+12h 09m 36s} (1950)
GRB_DEC:         -67.689d {-67d 41' 19"} (J2000),
                 -67.781d {-67d 46' 52"} (current),
                 -67.411d {-67d 24' 38"} (1950)
GRB_DATE:        17626 TJD;   239 DOY;   16/08/26
GRB_TIME:        22358.27 SOD {06:12:38.27} UT
TRIGGER_INDEX:   478
GRB_PHI:         -174.52 [deg]
GRB_THETA:         8.00 [deg]
DELTA_TIME:      -63.00 [sec]
TRIGGER_DUR:     12.160 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     10.44 [sigma]
IMAGE_SIGNIF:    9.26 [sigma]
LC_URL:          sw00709907000msb.lc
SUN_POSTN:       155.37d {+10h 21m 29s}  +10.24d {+10d 14' 28"}
SUN_DIST:         80.55 [deg]   Sun_angle= -1.9 [hr] (East of Sun)
MOON_POSTN:       77.37d {+05h 09m 28s}  +17.63d {+17d 37' 33"}
MOON_DIST:       112.29 [deg]
MOON_ILLUM:      38 [%]
GAL_COORDS:      299.22, -5.10 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      225.57,-57.21 [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 = 166.50,-6.94 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 26 Aug 16 06:18:14 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     709907,   Seg_Num: 0
POINT_RA:        183.080d {+12h 12m 19s} (J2000)
POINT_DEC:       -67.688d {-67d 41' 15"} (J2000)
POINT_ROLL:      332.335d
IMG_START_DATE:  17626 TJD;   239 DOY;   16/08/26
IMG_START_TIME:  22466.70 SOD {06:14:26.70} UT,   108.4 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        4.331
N_STARS:         190
X_OFFSET:        464 [pixels]
Y_OFFSET:        536 [pixels]
X_MAX:           1423 [pixels]
Y_MAX:           1495 [pixels]
DET_THRESH:      17
PHOTO_THRESH:    10
SL_URL:          sw00709907000msufc0108.fits
SUN_POSTN:       155.37d {+10h 21m 29s}  +10.24d {+10d 14' 26"}
SUN_DIST:         80.55 [deg]   Sun_angle= -1.9 [hr] (East of Sun)
MOON_POSTN:       77.39d {+05h 09m 33s}  +17.63d {+17d 37' 40"}
MOON_DIST:       112.28 [deg]
MOON_ILLUM:      38 [%]
GAL_COORDS:      299.22, -5.10 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      225.57,-57.21 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 26 Aug 16 06:18:43 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     709907,   Seg_Num: 0
POINT_RA:        183.080d {+12h 12m 19s} (J2000)
POINT_DEC:       -67.688d {-67d 41' 15"} (J2000)
POINT_ROLL:      332.335d
IMG_START_DATE:  17626 TJD;   239 DOY;   16/08/26
IMG_START_TIME:  22466.70 SOD {06:14:26.70} UT,   108.4 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        4.331
N_STARS:         190
X_OFFSET:        464 [pixels]
Y_OFFSET:        536 [pixels]
X_MAX:           1423 [pixels]
Y_MAX:           1495 [pixels]
DET_THRESH:      17
PHOTO_THRESH:    10
SL_URL:          sw00709907000msufc0108.fits
SUN_POSTN:       155.37d {+10h 21m 29s}  +10.24d {+10d 14' 25"}
SUN_DIST:         80.55 [deg]   Sun_angle= -1.9 [hr] (East of Sun)
MOON_POSTN:       77.39d {+05h 09m 34s}  +17.63d {+17d 37' 41"}
MOON_DIST:       112.28 [deg]
MOON_ILLUM:      38 [%]
GAL_COORDS:      299.22, -5.10 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      225.57,-57.21 [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:     Fri 26 Aug 16 06:19:52 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     709907,   Seg_Num: 0
POINT_RA:        183.080d {+12h 12m 19s} (J2000)
POINT_DEC:       -67.688d {-67d 41' 15"} (J2000)
ROLL:            332.335d
IMG_START_DATE:  17626 TJD;   239 DOY;   16/08/26
IMG_START_TIME:  22466.70 SOD {06:14:26.70} UT,   108.4 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     493884883
X_OFFSET:        968 [pixels]
Y_OFFSET:        954 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1128
Y_GRB_POS:       1114
BINNING_INDEX:   1
IM_URL:          sw00709907000msuni0125.fits
SUN_POSTN:       155.37d {+10h 21m 29s}  +10.24d {+10d 14' 24"}
SUN_DIST:         80.55 [deg]   Sun_angle= -1.9 [hr] (East of Sun)
MOON_POSTN:       77.40d {+05h 09m 37s}  +17.63d {+17d 37' 45"}
MOON_DIST:       112.28 [deg]
MOON_ILLUM:      38 [%]
GAL_COORDS:      299.22, -5.10 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      225.57,-57.21 [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:     Fri 26 Aug 16 06:20:10 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     709907,   Seg_Num: 0
POINT_RA:        183.080d {+12h 12m 19s} (J2000)
POINT_DEC:       -67.688d {-67d 41' 15"} (J2000)
ROLL:            332.335d
IMG_START_DATE:  17626 TJD;   239 DOY;   16/08/26
IMG_START_TIME:  22466.70 SOD {06:14:26.70} UT,   108.4 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     493884883
X_OFFSET:        968 [pixels]
Y_OFFSET:        954 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1128
Y_GRB_POS:       1114
BINNING_INDEX:   1
IM_URL:          sw00709907000msuni0125.fits
SUN_POSTN:       155.37d {+10h 21m 29s}  +10.24d {+10d 14' 24"}
SUN_DIST:         80.55 [deg]   Sun_angle= -1.9 [hr] (East of Sun)
MOON_POSTN:       77.41d {+05h 09m 38s}  +17.63d {+17d 37' 46"}
MOON_DIST:       112.28 [deg]
MOON_ILLUM:      38 [%]
GAL_COORDS:      299.22, -5.10 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      225.57,-57.21 [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:     Fri 26 Aug 16 06:25:27 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     709907,   Seg_Num: 0
POINT_RA:        183.083d {+12h 12m 20s} (J2000)
POINT_DEC:       -67.687d {-67d 41' 13"} (J2000)
POINT_ROLL:      332.330d
IMG_START_DATE:  17626 TJD;   239 DOY;   16/08/26
IMG_START_TIME:  22624.89 SOD {06:17:04.89} UT,   266.6 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.204
N_STARS:         190
X_OFFSET:        648 [pixels]
Y_OFFSET:        634 [pixels]
X_MAX:           1607 [pixels]
Y_MAX:           1593 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00709907000msufc0266.fits
SUN_POSTN:       155.37d {+10h 21m 30s}  +10.24d {+10d 14' 20"}
SUN_DIST:         80.55 [deg]   Sun_angle= -1.9 [hr] (East of Sun)
MOON_POSTN:       77.46d {+05h 09m 50s}  +17.63d {+17d 38' 03"}
MOON_DIST:       112.26 [deg]
MOON_ILLUM:      38 [%]
GAL_COORDS:      299.22, -5.10 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      225.57,-57.21 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 26 Aug 16 06:25:57 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     709907,   Seg_Num: 0
POINT_RA:        183.083d {+12h 12m 20s} (J2000)
POINT_DEC:       -67.687d {-67d 41' 13"} (J2000)
POINT_ROLL:      332.330d
IMG_START_DATE:  17626 TJD;   239 DOY;   16/08/26
IMG_START_TIME:  22624.89 SOD {06:17:04.89} UT,   266.6 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.204
N_STARS:         190
X_OFFSET:        648 [pixels]
Y_OFFSET:        634 [pixels]
X_MAX:           1607 [pixels]
Y_MAX:           1593 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00709907000msufc0266.fits
SUN_POSTN:       155.37d {+10h 21m 30s}  +10.24d {+10d 14' 19"}
SUN_DIST:         80.55 [deg]   Sun_angle= -1.9 [hr] (East of Sun)
MOON_POSTN:       77.46d {+05h 09m 52s}  +17.63d {+17d 38' 05"}
MOON_DIST:       112.26 [deg]
MOON_ILLUM:      38 [%]
GAL_COORDS:      299.22, -5.10 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      225.57,-57.21 [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:     Fri 26 Aug 16 06:26:51 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     709907,   Seg_Num: 0
POINT_RA:        183.083d {+12h 12m 20s} (J2000)
POINT_DEC:       -67.687d {-67d 41' 13"} (J2000)
ROLL:            332.330d
IMG_START_DATE:  17626 TJD;   239 DOY;   16/08/26
IMG_START_TIME:  22624.89 SOD {06:17:04.89} UT,   266.6 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     493885041
X_OFFSET:        968 [pixels]
Y_OFFSET:        954 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1128
Y_GRB_POS:       1114
BINNING_INDEX:   1
IM_URL:          sw00709907000msuni0283.fits
SUN_POSTN:       155.38d {+10h 21m 30s}  +10.24d {+10d 14' 18"}
SUN_DIST:         80.55 [deg]   Sun_angle= -1.9 [hr] (East of Sun)
MOON_POSTN:       77.47d {+05h 09m 54s}  +17.64d {+17d 38' 08"}
MOON_DIST:       112.26 [deg]
MOON_ILLUM:      38 [%]
GAL_COORDS:      299.22, -5.10 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      225.57,-57.21 [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:     Fri 26 Aug 16 06:27:12 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     709907,   Seg_Num: 0
POINT_RA:        183.083d {+12h 12m 20s} (J2000)
POINT_DEC:       -67.687d {-67d 41' 13"} (J2000)
ROLL:            332.330d
IMG_START_DATE:  17626 TJD;   239 DOY;   16/08/26
IMG_START_TIME:  22624.89 SOD {06:17:04.89} UT,   266.6 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     493885041
X_OFFSET:        968 [pixels]
Y_OFFSET:        954 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1128
Y_GRB_POS:       1114
BINNING_INDEX:   1
IM_URL:          sw00709907000msuni0283.fits
SUN_POSTN:       155.38d {+10h 21m 30s}  +10.24d {+10d 14' 18"}
SUN_DIST:         80.55 [deg]   Sun_angle= -1.9 [hr] (East of Sun)
MOON_POSTN:       77.48d {+05h 09m 55s}  +17.64d {+17d 38' 09"}
MOON_DIST:       112.26 [deg]
MOON_ILLUM:      38 [%]
GAL_COORDS:      299.22, -5.10 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      225.57,-57.21 [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 #19866
B. Mingo (U Leicester), H. A. Krimm (CRESST/GSFC/USRA), K. L. Page (U Leicester) and M. H. Siegel (PSU) report on behalf of the Swift Team:
At 06:12:38 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 160826A (trigger=709907). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 183.074, -67.689 which is
```
   RA(J2000) = 12h 12m 18s
   Dec(J2000) = -67d 41' 19"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a multi-peaked structure with a duration of about 30 sec. The peak count rate was ~1300 counts/sec (15-350 keV), at ~1 sec after the trigger.
The XRT began observing the field at 06:14:20.8 UT, 102.5 seconds after the BAT trigger. Using promptly downlinked data we find a bright, fading, uncatalogued X-ray source located at RA, Dec 183.11400, -67.66411 which is equivalent to:
```
   RA(J2000)  = 12h 12m 27.36s
   Dec(J2000) = -67d 39' 50.8"
```
with an uncertainty of 3.8 arcseconds (radius, 90% containment). This location is 104 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.
A power-law fit to a spectrum formed from promptly downlinked event data gives a column density consistent with the Galactic value of 4.59 x 10^21 cm^-2 (Willingale et al. 2013).
The initial flux in the 2.5 s image was 5.77e-10 erg cm^-2 s^-1 (0.2-10 keV).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 108 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. Because of the density of catalogued stars, further analysis is required to report an upper limit for any afterglow in the sub-image. The 8'x8' region for the list of sources generated on-board covers 100% of the XRT error circle. Because of the density of catalogued stars, further analysis is required to report an upper limit for any afterglow in the region. No correction has been made for the expected extinction corresponding to E(B-V) of 0.47.
Burst Advocate for this burst is B. Mingo (bm188 AT le.ac.uk). 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:     Fri 26 Aug 16 06:32:41 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     709907,   Seg_Num: 0
POINT_RA:        183.083d {+12h 12m 20s} (J2000)
POINT_DEC:       -67.687d {-67d 41' 13"} (J2000)
POINT_ROLL:      332.330d
IMG_START_DATE:  17626 TJD;   239 DOY;   16/08/26
IMG_START_TIME:  23228.47 SOD {06:27:08.47} UT,   870.2 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.851
N_STARS:         190
X_OFFSET:        408 [pixels]
Y_OFFSET:        394 [pixels]
X_MAX:           1847 [pixels]
Y_MAX:           1833 [pixels]
DET_THRESH:      16
PHOTO_THRESH:    9
SL_URL:          sw00709907000msufc0870.fits
SUN_POSTN:       155.38d {+10h 21m 31s}  +10.24d {+10d 14' 13"}
SUN_DIST:         80.54 [deg]   Sun_angle= -1.9 [hr] (East of Sun)
MOON_POSTN:       77.53d {+05h 10m 08s}  +17.64d {+17d 38' 27"}
MOON_DIST:       112.24 [deg]
MOON_ILLUM:      37 [%]
GAL_COORDS:      299.22, -5.10 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      225.57,-57.21 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 26 Aug 16 06:33:09 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     709907,   Seg_Num: 0
POINT_RA:        183.083d {+12h 12m 20s} (J2000)
POINT_DEC:       -67.687d {-67d 41' 13"} (J2000)
POINT_ROLL:      332.330d
IMG_START_DATE:  17626 TJD;   239 DOY;   16/08/26
IMG_START_TIME:  23228.47 SOD {06:27:08.47} UT,   870.2 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.851
N_STARS:         190
X_OFFSET:        408 [pixels]
Y_OFFSET:        394 [pixels]
X_MAX:           1847 [pixels]
Y_MAX:           1833 [pixels]
DET_THRESH:      16
PHOTO_THRESH:    9
SL_URL:          sw00709907000msufc0870.fits
SUN_POSTN:       155.38d {+10h 21m 31s}  +10.24d {+10d 14' 13"}
SUN_DIST:         80.54 [deg]   Sun_angle= -1.9 [hr] (East of Sun)
MOON_POSTN:       77.54d {+05h 10m 09s}  +17.64d {+17d 38' 29"}
MOON_DIST:       112.24 [deg]
MOON_ILLUM:      37 [%]
GAL_COORDS:      299.22, -5.10 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      225.57,-57.21 [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:     Fri 26 Aug 16 06:34:18 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     709907,   Seg_Num: 0
POINT_RA:        183.083d {+12h 12m 20s} (J2000)
POINT_DEC:       -67.687d {-67d 41' 13"} (J2000)
ROLL:            332.330d
IMG_START_DATE:  17626 TJD;   239 DOY;   16/08/26
IMG_START_TIME:  23228.47 SOD {06:27:08.47} UT,   870.2 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     493885645
X_OFFSET:        967 [pixels]
Y_OFFSET:        953 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1127
Y_GRB_POS:       1113
BINNING_INDEX:   1
IM_URL:          sw00709907000msuni0887.fits
SUN_POSTN:       155.38d {+10h 21m 31s}  +10.24d {+10d 14' 12"}
SUN_DIST:         80.54 [deg]   Sun_angle= -1.9 [hr] (East of Sun)
MOON_POSTN:       77.55d {+05h 10m 12s}  +17.64d {+17d 38' 32"}
MOON_DIST:       112.24 [deg]
MOON_ILLUM:      37 [%]
GAL_COORDS:      299.22, -5.10 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      225.57,-57.21 [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:     Fri 26 Aug 16 06:34:40 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     709907,   Seg_Num: 0
POINT_RA:        183.083d {+12h 12m 20s} (J2000)
POINT_DEC:       -67.687d {-67d 41' 13"} (J2000)
ROLL:            332.330d
IMG_START_DATE:  17626 TJD;   239 DOY;   16/08/26
IMG_START_TIME:  23228.47 SOD {06:27:08.47} UT,   870.2 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     493885645
X_OFFSET:        967 [pixels]
Y_OFFSET:        953 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1127
Y_GRB_POS:       1113
BINNING_INDEX:   1
IM_URL:          sw00709907000msuni0887.fits
SUN_POSTN:       155.38d {+10h 21m 31s}  +10.24d {+10d 14' 12"}
SUN_DIST:         80.54 [deg]   Sun_angle= -1.9 [hr] (East of Sun)
MOON_POSTN:       77.55d {+05h 10m 13s}  +17.64d {+17d 38' 34"}
MOON_DIST:       112.24 [deg]
MOON_ILLUM:      37 [%]
GAL_COORDS:      299.22, -5.10 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      225.57,-57.21 [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 #19868
P.A. Evans (U. Leicester), A. D'Ai (INAF-IASFPA), A. Maselli (INAF-IASFPA), A. Melandri (INAF-OAB), J.A. Kennea (PSU), B. Sbarufatti (INAF-OAB/PSU), D.N. Burrows (PSU), S.L. Gibson (U. Leicester), J.P. Osborne (U. Leicester) and B. Mingo report on behalf of the Swift-XRT team:
We have analysed 6.5 ks of XRT data for GRB 160826A (Mingo et al. GCN Circ. 19866), from 93 s to 22.1 ks after the BAT trigger. The data comprise 114 s in Windowed Timing (WT) mode (the first 5 s were taken while Swift was slewing) with the remainder in Photon Counting (PC) mode. The refined XRT position is RA, Dec = 183.1127, -67.6639 which is equivalent to:
```
RA (J2000): 12 12 27.05
Dec(J2000): -67 39 50.0
```
with an uncertainty of 3.5 arcsec (radius, 90% confidence).
The light curve can be modelled with a power-law decay with a decay index of alpha=1.64 (+0.06, -0.05).
A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 1.68 (+0.31, -0.28). The best-fitting absorption column is 9.1 (+3.3, -2.7) x 10^21 cm^-2, in excess of the Galactic value of 4.6 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 5.7 x 10^-11 (8.5 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     9.1 (+3.3, -2.7) x 10^21 cm^-2
Galactic foreground: 4.6 x 10^21 cm^-2
Excess significance: 2.7 sigma
Photon index:	     1.68 (+0.31, -0.28)
```
If the light curve continues to decay with a power-law decay index of 1.64, the count rate at T+24 hours will be 2.1 x 10^-4 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.2 x 10^-14 (1.7 x 10^-14) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00709907.
This circular is an official product of the Swift-XRT team.
GCN Circular #19871
S. J. LaPorte (PSU) and B. Mingo (U. Leicester) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 160826A 109 s after the BAT trigger (Mingo et al., GCN Circ. 19866). No optical afterglow consistent with the XRT position (Mingo et al. GCN Circ. 19868) 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           109          259          147         >21.1
u_FC               267          517          246         >19.8
white              109         1195          353         >22.1
v                  597         1245           78         >19.8
b                  523         1170           58         >20.2
u                  267         4893          340         >19.8
w1                 648         1290           74         >19.0
m2                 622         1269           78         >19.3
w2                 573         1220           78         >19.9
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.47 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #19872
M. Stamatikos (OSU), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), B. Mingo (U Leicester), D. M. Palmer (LANL), T. Sakamoto (AGU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):
Using the data set from T-239 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 160826A (trigger #709907) (Mingo, et al., GCN Circ. 19866). The BAT ground-calculated position is RA, Dec = 183.120, -67.664 deg which is
```
    RA(J2000)  =  12h 12m 28.8s
    Dec(J2000) = -67d 39' 51.7"
```
with an uncertainty of 2.6 arcmin, (radius, sys+stat, 90% containment). The partial coding was 100%.
The mask-weighted light curve shows a single, rough FRED-like peak starting at T+0 sec, peaking at about T+5 sec and decaying to near background by T+20 sec. This is followed by low-level emission out to about T+70 sec. T90 (15-350 keV) is 52.6 +- 14.5 sec (estimated error including systematics).
The time-averaged spectrum from T+3.85 to T+61.58 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.54 +- 0.29. The fluence in the 15-150 keV band is 4.9 +- 0.9 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+4.64 sec in the 15-150 keV band is 0.4 +- 0.1 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/709907/BA/

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Jochen Greiner, last update: 26-Aug-2016 [Disclaimer]