Gamma-ray Burst 160506A

(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:     Fri 06 May 16 03:30:15 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     685245,   Seg_Num: 0
GRB_RA:          265.774d {+17h 43m 06s} (J2000),
                 266.077d {+17h 44m 19s} (current),
                 264.845d {+17h 39m 23s} (1950)
GRB_DEC:         -46.117d {-46d 07' 00"} (J2000),
                 -46.123d {-46d 07' 23"} (current),
                 -46.094d {-46d 05' 38"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       9770 [cnts]    Image_Peak=271 [image_cnts]
TRIGGER_DUR:     3.072 [sec] 
TRIGGER_INDEX:   474     E_range: 25-100 keV
BKG_INTEN:       88914 [cnts]
BKG_TIME:        12511.77 SOD {03:28:31.77} UT
BKG_DUR:         32 [sec]
GRB_DATE:        17514 TJD;   127 DOY;   16/05/06
GRB_TIME:        12555.86 SOD {03:29:15.86} UT
GRB_PHI:         -15.94 [deg]
GRB_THETA:        17.16 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     10.09 [sigma]
IMAGE_SIGNIF:    7.19 [sigma]
MERIT_PARAMS:     +1  +0  +0  +2  +2  -3  +0  +1 +69  +0 
SUN_POSTN:        43.58d {+02h 54m 19s}  +16.64d {+16d 38' 18"}
SUN_DIST:        134.11 [deg]   Sun_angle= 9.2 [hr] (West of Sun)
MOON_POSTN:       35.65d {+02h 22m 37s}  +10.27d {+10d 16' 00"}
MOON_DIST:       124.26 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      344.99, -8.48 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      266.82,-22.72 [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 = 308.81,16.74 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 06 May 16 03:31:25 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     685245,   Seg_Num: 0
GRB_RA:          265.8486d {+17h 43m 23.66s} (J2000),
                 266.1525d {+17h 44m 36.59s} (current),
                 264.9195d {+17h 39m 40.67s} (1950)
GRB_DEC:         -46.1329d {-46d 07' 58.4"} (J2000),
                 -46.1392d {-46d 08' 21.2"} (current),
                 -46.1105d {-46d 06' 37.7"} (1950)
GRB_ERROR:       5.0 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       2.68e-09 [erg/cm2/sec]
GRB_SIGNIF:      8.88 [sigma]
IMG_START_DATE:  17514 TJD;   127 DOY;   16/05/06
IMG_START_TIME:  12650.65 SOD {03:30:50.65} UT,   94.8 [sec] since BAT Trigger Time
TAM[0-3]:        327.67 237.23 261.59 243.66
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:        43.58d {+02h 54m 19s}  +16.64d {+16d 38' 18"}
SUN_DIST:        134.06 [deg]   Sun_angle= 9.2 [hr] (West of Sun)
MOON_POSTN:       35.67d {+02h 22m 40s}  +10.27d {+10d 16' 12"}
MOON_DIST:       124.22 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      345.01, -8.53 [deg] galactic lon,lat of the burst
ECL_COORDS:      266.88,-22.74 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 3.26 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 06 May 16 03:31:35 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     685245,   Seg_Num: 0
GRB_RA:          265.8486d {+17h 43m 23.6s} (J2000),
                 266.1525d {+17h 44m 36.5s} (current),
                 264.9195d {+17h 39m 40.6s} (1950)
GRB_DEC:         -46.1329d {-46d 07' 58.4"} (J2000),
                 -46.1392d {-46d 08' 21.2"} (current),
                 -46.1105d {-46d 06' 37.7"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       79 [cnts]
IMG_START_DATE:  17514 TJD;   127 DOY;   16/05/06
IMG_START_TIME:  12650.65 SOD {03:30:50.65} UT,   94.8 [sec] since BAT Trigger Time
CENTROID_X:      217.71,  raw= 218  [pixels]
CENTROID_Y:      305.90,  raw= 306  [pixels]
ROLL:            115.96 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   19.09
GRB_POS_XRT_Z:   -206.46
IMAGE_URL:       sw00685245000msxps_rw.img
SUN_POSTN:        43.58d {+02h 54m 19s}  +16.64d {+16d 38' 19"}
SUN_DIST:        134.06 [deg]   Sun_angle= 9.2 [hr] (West of Sun)
MOON_POSTN:       35.67d {+02h 22m 40s}  +10.27d {+10d 16' 14"}
MOON_DIST:       124.22 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      345.01, -8.53 [deg] galactic lon,lat of the burst
ECL_COORDS:      266.88,-22.74 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 06 May 16 03:31:39 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     685245,   Seg_Num: 0
GRB_RA:          265.8486d {+17h 43m 23.6s} (J2000),
                 266.1525d {+17h 44m 36.5s} (current),
                 264.9195d {+17h 39m 40.6s} (1950)
GRB_DEC:         -46.1329d {-46d 07' 58.4"} (J2000),
                 -46.1392d {-46d 08' 21.2"} (current),
                 -46.1105d {-46d 06' 37.7"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       79 [cnts]
IMG_START_DATE:  17514 TJD;   127 DOY;   16/05/06
IMG_START_TIME:  12650.65 SOD {03:30:50.65} UT,   94.8 [sec] since BAT Trigger Time
CENTROID_X:      217.71,  raw= 218  [pixels]
CENTROID_Y:      305.90,  raw= 306  [pixels]
ROLL:            115.96 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   19.09
GRB_POS_XRT_Z:   -206.46
IMAGE_URL:       sw00685245000msxps_rw.img
SUN_POSTN:        43.58d {+02h 54m 19s}  +16.64d {+16d 38' 19"}
SUN_DIST:        134.06 [deg]   Sun_angle= 9.2 [hr] (West of Sun)
MOON_POSTN:       35.67d {+02h 22m 40s}  +10.27d {+10d 16' 15"}
MOON_DIST:       124.22 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      345.01, -8.53 [deg] galactic lon,lat of the burst
ECL_COORDS:      266.88,-22.74 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 06 May 16 03:33:02 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     685245,   Seg_Num: 0
GRB_RA:          265.774d {+17h 43m 06s} (J2000),
                 266.077d {+17h 44m 19s} (current),
                 264.845d {+17h 39m 23s} (1950)
GRB_DEC:         -46.117d {-46d 07' 00"} (J2000),
                 -46.123d {-46d 07' 23"} (current),
                 -46.094d {-46d 05' 38"} (1950)
GRB_DATE:        17514 TJD;   127 DOY;   16/05/06
GRB_TIME:        12555.86 SOD {03:29:15.86} UT
TRIGGER_INDEX:   474
GRB_PHI:         -15.94 [deg]
GRB_THETA:        17.16 [deg]
DELTA_TIME:      70.00 [sec]
TRIGGER_DUR:     3.072 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     10.09 [sigma]
IMAGE_SIGNIF:    7.19 [sigma]
LC_URL:          sw00685245000msb.lc
SUN_POSTN:        43.58d {+02h 54m 19s}  +16.64d {+16d 38' 20"}
SUN_DIST:        134.11 [deg]   Sun_angle= 9.2 [hr] (West of Sun)
MOON_POSTN:       35.68d {+02h 22m 44s}  +10.27d {+10d 16' 29"}
MOON_DIST:       124.29 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      344.99, -8.48 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      266.82,-22.72 [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 = 308.81,16.74 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 06 May 16 03:35:33 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     685245,   Seg_Num: 0
POINT_RA:        265.771d {+17h 43m 05s} (J2000)
POINT_DEC:       -46.113d {-46d 06' 47"} (J2000)
POINT_ROLL:      115.959d
IMG_START_DATE:  17514 TJD;   127 DOY;   16/05/06
IMG_START_TIME:  12657.37 SOD {03:30:57.37} UT,   101.5 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.193
N_STARS:         190
X_OFFSET:        288 [pixels]
Y_OFFSET:        328 [pixels]
X_MAX:           1727 [pixels]
Y_MAX:           1767 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00685245000msufc0101.fits
SUN_POSTN:        43.58d {+02h 54m 20s}  +16.64d {+16d 38' 21"}
SUN_DIST:        134.12 [deg]   Sun_angle= 9.2 [hr] (West of Sun)
MOON_POSTN:       35.71d {+02h 22m 50s}  +10.28d {+10d 16' 54"}
MOON_DIST:       124.31 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      344.99, -8.47 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      266.82,-22.72 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 06 May 16 03:36:01 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     685245,   Seg_Num: 0
POINT_RA:        265.771d {+17h 43m 05s} (J2000)
POINT_DEC:       -46.113d {-46d 06' 47"} (J2000)
POINT_ROLL:      115.959d
IMG_START_DATE:  17514 TJD;   127 DOY;   16/05/06
IMG_START_TIME:  12657.37 SOD {03:30:57.37} UT,   101.5 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.193
N_STARS:         190
X_OFFSET:        288 [pixels]
Y_OFFSET:        328 [pixels]
X_MAX:           1727 [pixels]
Y_MAX:           1767 [pixels]
DET_THRESH:      9
PHOTO_THRESH:    4
SL_URL:          sw00685245000msufc0101.fits
SUN_POSTN:        43.58d {+02h 54m 20s}  +16.64d {+16d 38' 22"}
SUN_DIST:        134.12 [deg]   Sun_angle= 9.2 [hr] (West of Sun)
MOON_POSTN:       35.71d {+02h 22m 51s}  +10.28d {+10d 16' 59"}
MOON_DIST:       124.32 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      344.99, -8.47 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      266.82,-22.72 [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 06 May 16 03:37:26 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     685245,   Seg_Num: 0
POINT_RA:        265.771d {+17h 43m 05s} (J2000)
POINT_DEC:       -46.113d {-46d 06' 47"} (J2000)
ROLL:            115.959d
IMG_START_DATE:  17514 TJD;   127 DOY;   16/05/06
IMG_START_TIME:  12657.37 SOD {03:30:57.37} UT,   101.5 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     484198273
X_OFFSET:        1153 [pixels]
Y_OFFSET:        651 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1313
Y_GRB_POS:       811
BINNING_INDEX:   1
IM_URL:          sw00685245000msuni0118.fits
SUN_POSTN:        43.58d {+02h 54m 20s}  +16.64d {+16d 38' 23"}
SUN_DIST:        134.12 [deg]   Sun_angle= 9.2 [hr] (West of Sun)
MOON_POSTN:       35.73d {+02h 22m 55s}  +10.29d {+10d 17' 14"}
MOON_DIST:       124.33 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      344.99, -8.47 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      266.82,-22.72 [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 06 May 16 03:37:44 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     685245,   Seg_Num: 0
POINT_RA:        265.771d {+17h 43m 05s} (J2000)
POINT_DEC:       -46.113d {-46d 06' 47"} (J2000)
ROLL:            115.959d
IMG_START_DATE:  17514 TJD;   127 DOY;   16/05/06
IMG_START_TIME:  12657.37 SOD {03:30:57.37} UT,   101.5 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     484198273
X_OFFSET:        1153 [pixels]
Y_OFFSET:        651 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1313
Y_GRB_POS:       811
BINNING_INDEX:   1
IM_URL:          sw00685245000msuni0118.fits
SUN_POSTN:        43.58d {+02h 54m 20s}  +16.64d {+16d 38' 23"}
SUN_DIST:        134.12 [deg]   Sun_angle= 9.2 [hr] (West of Sun)
MOON_POSTN:       35.73d {+02h 22m 55s}  +10.29d {+10d 17' 17"}
MOON_DIST:       124.33 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      344.99, -8.47 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      266.82,-22.72 [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 06 May 16 03:48:04 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     685245,   Seg_Num: 0
POINT_RA:        265.771d {+17h 43m 05s} (J2000)
POINT_DEC:       -46.111d {-46d 06' 37"} (J2000)
POINT_ROLL:      115.957d
IMG_START_DATE:  17514 TJD;   127 DOY;   16/05/06
IMG_START_TIME:  13416.64 SOD {03:43:36.64} UT,   860.8 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.746
N_STARS:         190
X_OFFSET:        593 [pixels]
Y_OFFSET:        91 [pixels]
X_MAX:           2032 [pixels]
Y_MAX:           1530 [pixels]
DET_THRESH:      8
PHOTO_THRESH:    3
SL_URL:          sw00685245000msufc0860.fits
SUN_POSTN:        43.59d {+02h 54m 22s}  +16.64d {+16d 38' 30"}
SUN_DIST:        134.12 [deg]   Sun_angle= 9.2 [hr] (West of Sun)
MOON_POSTN:       35.84d {+02h 23m 21s}  +10.32d {+10d 19' 02"}
MOON_DIST:       124.42 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      345.00, -8.47 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      266.82,-22.72 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 06 May 16 03:48:32 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     685245,   Seg_Num: 0
POINT_RA:        265.771d {+17h 43m 05s} (J2000)
POINT_DEC:       -46.111d {-46d 06' 37"} (J2000)
POINT_ROLL:      115.957d
IMG_START_DATE:  17514 TJD;   127 DOY;   16/05/06
IMG_START_TIME:  13416.64 SOD {03:43:36.64} UT,   860.8 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.746
N_STARS:         190
X_OFFSET:        593 [pixels]
Y_OFFSET:        91 [pixels]
X_MAX:           2032 [pixels]
Y_MAX:           1530 [pixels]
DET_THRESH:      8
PHOTO_THRESH:    3
SL_URL:          sw00685245000msufc0860.fits
SUN_POSTN:        43.59d {+02h 54m 22s}  +16.64d {+16d 38' 30"}
SUN_DIST:        134.12 [deg]   Sun_angle= 9.2 [hr] (West of Sun)
MOON_POSTN:       35.84d {+02h 23m 22s}  +10.32d {+10d 19' 07"}
MOON_DIST:       124.43 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      345.00, -8.47 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      266.82,-22.72 [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 06 May 16 03:48:44 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     685245,   Seg_Num: 0
GRB_RA:          265.8484d {+17h 43m 23.61s} (J2000),
                 266.1523d {+17h 44m 36.54s} (current),
                 264.9193d {+17h 39m 40.62s} (1950)
GRB_DEC:         -46.1340d {-46d 08' 02.4"} (J2000),
                 -46.1403d {-46d 08' 25.2"} (current),
                 -46.1116d {-46d 06' 41.7"} (1950)
GRB_ERROR:       2.0 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  17514 TJD;   127 DOY;   16/05/06
IMG_START_TIME:  13081.00 SOD {03:38:01.00} UT,   525.1 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:        43.59d {+02h 54m 22s}  +16.64d {+16d 38' 30"}
SUN_DIST:        134.07 [deg]   Sun_angle= 9.2 [hr] (West of Sun)
MOON_POSTN:       35.84d {+02h 23m 23s}  +10.32d {+10d 19' 09"}
MOON_DIST:       124.37 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      345.00, -8.53 [deg] galactic lon,lat of the burst
ECL_COORDS:      266.88,-22.74 [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 0.58% < P(seren) < 1.1%.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 06 May 16 03:49:18 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     685245,   Seg_Num: 0
POINT_RA:        265.771d {+17h 43m 05s} (J2000)
POINT_DEC:       -46.111d {-46d 06' 37"} (J2000)
ROLL:            115.957d
IMG_START_DATE:  17514 TJD;   127 DOY;   16/05/06
IMG_START_TIME:  13416.64 SOD {03:43:36.64} UT,   860.8 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     484199032
X_OFFSET:        1152 [pixels]
Y_OFFSET:        650 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1312
Y_GRB_POS:       810
BINNING_INDEX:   1
IM_URL:          sw00685245000msuni0877.fits
SUN_POSTN:        43.59d {+02h 54m 22s}  +16.64d {+16d 38' 31"}
SUN_DIST:        134.12 [deg]   Sun_angle= 9.2 [hr] (West of Sun)
MOON_POSTN:       35.85d {+02h 23m 24s}  +10.32d {+10d 19' 14"}
MOON_DIST:       124.43 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      345.00, -8.47 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      266.82,-22.72 [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 06 May 16 03:49:35 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     685245,   Seg_Num: 0
POINT_RA:        265.771d {+17h 43m 05s} (J2000)
POINT_DEC:       -46.111d {-46d 06' 37"} (J2000)
ROLL:            115.957d
IMG_START_DATE:  17514 TJD;   127 DOY;   16/05/06
IMG_START_TIME:  13416.64 SOD {03:43:36.64} UT,   860.8 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     484199032
X_OFFSET:        1152 [pixels]
Y_OFFSET:        650 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1312
Y_GRB_POS:       810
BINNING_INDEX:   1
IM_URL:          sw00685245000msuni0877.fits
SUN_POSTN:        43.59d {+02h 54m 22s}  +16.64d {+16d 38' 31"}
SUN_DIST:        134.12 [deg]   Sun_angle= 9.2 [hr] (West of Sun)
MOON_POSTN:       35.85d {+02h 23m 25s}  +10.32d {+10d 19' 17"}
MOON_DIST:       124.44 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      345.00, -8.47 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      266.82,-22.72 [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 #19394
L. M. Z. Hagen (PSU), S. D. Barthelmy (GSFC), H. A. Krimm (CRESST/GSFC/USRA), F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL) and M. H. Siegel (PSU) report on behalf of the Swift Team:
At 03:29:15 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 160506A (trigger=685245). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 265.774, -46.117 which is
```
   RA(J2000)  =  17h 43m 06s
   Dec(J2000) = -46d 07' 00"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows broad peak with a total duration of about 50 sec. The peak count rate was ~1200 counts/sec (15-350 keV), at ~0 sec after the trigger.
The XRT began observing the field at 03:30:50.6 UT, 94.8 seconds after the BAT trigger. Using promptly downlinked data we find a bright, fading, uncatalogued X-ray source with an enhanced position: RA, Dec 265.8484, -46.1340 which is equivalent to:
```
   RA(J2000)  = 17h 43m 23.60s
   Dec(J2000) = -46d 08' 02.3"
```
with an uncertainty of 2.0 arcseconds (radius, 90% containment). This location is 195 arcseconds from the BAT onboard position, outside 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 in excess of the Galactic value (2.67 x 10^21 cm^-2, Willingale et al. 2013), with an excess column of 4.8 (+2.85/-2.47) x 10^21 cm^-2 (90% confidence).
The initial flux in the 2.5 s image was 2.68e-09 erg cm^-2 s^-1 (0.2-10 keV).
UVOT took a finding chart exposure of 250 seconds with the U filter starting 101 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 upper limit has been 19.6 mag. The 8'x8' region for the list of sources generated on-board covers 100% of the XRT error circle. The typical upper limit has been 18.0 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.26.
Burst Advocate for this burst is L. M. Z. Hagen (lea.zernow.hagen 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 Circular #19395
J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) report on behalf of the Swift-XRT team.
Using 1815 s of XRT Photon Counting mode data and 1 UVOT images for GRB 160506A, 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 = 265.84841, -46.13410 which is equivalent to:
```
RA (J2000): 17h 43m 23.62s
Dec (J2000): -46d 08' 02.8"
```
with an uncertainty of 2.2 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 #19396
F. Knust, C. Delvaux, J. Greiner (all MPE Garching) report on behalf of the GROND team:
We observed the field of GRB 160506A (Swift trigger 685245; Hagen et al., GCN #19394) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2 m MPG telescope at ESO La Silla Observatory (Chile).
Observations started at 06:45 UT on 2016-05-06, 3.25 hrs after the GRB trigger. They were performed through substantial cirrus at an average seeing of 2.1" and at an average airmass of 1.1.
We do not detect any source within the Swift-XRT error circle reported by Osborne et al. (GCN #19395) down to
```
g' > 20.9 mag,
r' > 22.1 mag,
i' > 21.5 mag,
z' > 21.7 mag,
J > 19.4 mag,
H > 19.1 mag, and
K > 17.2 mag.
(all in AB),
```
but we see two faint sources north-east and sout-west of the XRT error circle, each about 4 arcsec away from the XRT centroid.
Given magnitudes are calibrated against USNO as well as 2MASS field stars and are not corrected for the expected Galactic foreground extinction corresponding to a reddening of E_(B-V)=0.26 mag in the direction of the burst (Schlegel et al. 1998).
GCN Circular #19397
T. Sakamoto (AGU), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), L. M. Z. Hagen (PSU), 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-239 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 160506A (trigger #685245) (Hagen, et al., GCN Circ. 19394). The BAT ground-calculated position is RA, Dec = 265.857, -46.127 deg which is
```
    RA(J2000)  =  17h 43m 25.6s
    Dec(J2000) = -46d 07' 36.1"
```
with an uncertainty of 1.6 arcmin, (radius, sys+stat, 90% containment). The partial coding was 100%.
The mask-weighted light curve shows a long and complex structure. The emission starts at T-10 sec, and continues with multiple peaks out to about T+275 sec. The highest count rate is at T+100 sec. The peaks after the slew ended at T+94.8 sec are also seen as flares in the XRT. T90 (15-350 keV) is 254.5 +- 24.9 sec (estimated error including systematics).
The time-averaged spectrum from T-8.33 to T+267.03 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.09 +- 0.21. The fluence in the 15-150 keV band is 1.5 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+98.80 sec in the 15-150 keV band is 0.4 +- 0.3 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/685245/BA/
GCN Circular #19398
L. M. Z. Hagen (PSU) reports on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 160506A 102 s after the BAT trigger (Hagen et al., GCN Circ. 19394). No optical afterglow consistent with the XRT position (Osborne et al. GCN Circ. 19395) 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

v                  407         2279          233        >19.36
b                  357         2229          252        >20.37
u_FC               101          351          245        >20.13
u                  101         2353          626        >20.58
uvw1               457         2329          233        >19.75
uvm2               432         2304          233        >19.52
uvw2               383         2255          252        >19.86
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.26 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #19399
J.A. Kennea (PSU), P.A. Evans (U. Leicester), S.L. Gibson (U. Leicester), J.P. Osborne (U. Leicester), A. D'Ai (INAF-IASFPA), A. Maselli (INAF-IASFPA), A. Melandri (INAF-OAB), B. Sbarufatti (INAF-OAB/PSU), D.N. Burrows (PSU) and L.M.Z. Hagen report on behalf of the Swift-XRT team:
We have analysed 7.4 ks of XRT data for GRB 160506A (Hagen et al. GCN Circ. 19394), from 86 s to 36.2 ks after the BAT trigger. The data comprise 422 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 Osborne et al. (GCN Circ. 19395).
The late-time light curve (from T0+5.6 ks) can be modelled with a power-law decay with a decay index of alpha=0.54 (+0.22, -0.21).
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.65 (+/-0.05). The best-fitting absorption column is 7.1 (+/-0.5) x 10^21 cm^-2, in excess of the Galactic value of 2.7 x 10^21 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 2.11 (+0.21, -0.20) and a best-fitting absorption column of 7.9 (+1.7, -1.5) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 4.3 x 10^-11 (8.2 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     7.9 (+1.7, -1.5) x 10^21 cm^-2
Galactic foreground: 2.7 x 10^21 cm^-2
Excess significance: 5.9 sigma
Photon index:	     2.11 (+0.21, -0.20)
```
If the light curve continues to decay with a power-law decay index of 0.54, the count rate at T+24 hours will be 0.013 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 5.4 x 10^-13 (1.0 x 10^-12) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00685245.
This circular is an official product of the Swift-XRT team.
GCN Circular #19400
K. L. Murata (Nagoya U.), Y.-H. Lee, B.-C. Koo (Seoul National U.), and T. Nagayama (Kagoshima U.)
We observed the field of GRB 160506A ( Hagen et al., GCN Circular #19394) with the near-infrared (J, H, Ks) simultaneous imaging camera SIRIUS attached to 1.4 m telescope IRSF ( InfraRed Survey Facility) in Sutherland observatory, South Africa. We observed with a narrow band filter with double transmissions at 1.189 um and 1.644 um.
The observations started on 2016-05-06 04:18:47 UT (~ 49 min. after the burst). We could not detect the afterglow within the XRT error circle reported in the GCN circular. We have obtained the following preliminary upper limits (Vega magnitude system):
```
 M_1.189um > 17.3 mag
 M_1.644um > 16.6 mag
```
Given magnitudes of M_1.189um and M_1.644um were calibrated against J band and H band of 2MASS point sources in this field, respectively. The upper limits were determined as the magnitudes of the faintest star within 1 arcmin from the XRT position.
This observation was carried out by IRSF and OISTER collaboration.
GCN Circular #19402
Klotz A., Turpin D., Atteia J.L. (CNRS-OMP-IRAP), Boer, M., Laugier, R. (CNRS-ARTEMIS), Gendre B. (UVI - Etelman Obs.) report:
We imaged the field of GRB 160506A detected by SWIFT (trigger 685245) with the TAROT robotic telescope (D=25cm) located at the European Southern Observatory, La Silla observatory, Chile.
The observations started 62.1s after the GRB trigger (14.0s after the notice). The elevation of the field increased from 41 degrees above horizon but clouds were presents in the sky.
The first image is trailed with a duration of 60.0s (see the description in Klotz et al., 2006, A&A 451, L39). We do not detect any OT with a limiting magnitude of: t0+62.1s to t0+122.1s : Rlim = 12.7
Then the observations were stopped due to the bad weather and start again 39 minutes later. We co-added a series of exposures: t0+2366s to t0+3314s : Rlim = 16.7
Magnitudes were estimated with the nearby NOMAD1 stars and are not corrected for galactic dust extinction.

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Jochen Greiner, last update: 08-May-2016 [Disclaimer]