Gamma-ray Burst 110808A

(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:     Mon 08 Aug 11 06:19:52 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     458918,   Seg_Num: 0
GRB_RA:           57.264d {+03h 49m 03s} (J2000),
                  57.360d {+03h 49m 26s} (current),
                  56.851d {+03h 47m 24s} (1950)
GRB_DEC:         -44.179d {-44d 10' 42"} (J2000),
                 -44.144d {-44d 08' 36"} (current),
                 -44.330d {-44d 19' 47"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       23572 [cnts]    Image_Peak=426 [image_cnts]
TRIGGER_DUR:     8.192 [sec] 
TRIGGER_INDEX:   477     E_range: 25-100 keV
BKG_INTEN:       170331 [cnts]
BKG_TIME:        22640.76 SOD {06:17:20.76} UT
BKG_DUR:         64 [sec]
GRB_DATE:        15781 TJD;   220 DOY;   11/08/08
GRB_TIME:        22734.20 SOD {06:18:54.20} UT
GRB_PHI:         170.26 [deg]
GRB_THETA:        29.28 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     10.00 [sigma]
IMAGE_SIGNIF:    7.19 [sigma]
MERIT_PARAMS:     +1  +0  +0  +3  +2  -3  +0  +0  +8  +0 
SUN_POSTN:       137.85d {+09h 11m 23s}  +16.22d {+16d 13' 20"}
SUN_DIST:         94.63 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:      246.65d {+16h 26m 37s}  -22.96d {-22d 57' 41"}
MOON_DIST:       112.36 [deg]
MOON_ILLUM:      70 [%]
GAL_COORDS:      250.54,-50.69 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       35.47,-61.56 [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 = 62.92,-19.23 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 08 Aug 11 06:21:17 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     458918,   Seg_Num: 0
GRB_RA:           57.2659d {+03h 49m 03.81s} (J2000),
                  57.3617d {+03h 49m 26.81s} (current),
                  56.8532d {+03h 47m 24.75s} (1950)
GRB_DEC:         -44.1948d {-44d 11' 41.2"} (J2000),
                 -44.1599d {-44d 09' 35.7"} (current),
                 -44.3462d {-44d 20' 46.2"} (1950)
GRB_ERROR:       6.3 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       5.42e-10 [erg/cm2/sec]
GRB_SIGNIF:      5.29 [sigma]
IMG_START_DATE:  15781 TJD;   220 DOY;   11/08/08
IMG_START_TIME:  22845.06 SOD {06:20:45.06} UT,   110.9 [sec] since BAT Trigger Time
TAM[0-3]:        327.67 237.20 261.41 243.38
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       137.85d {+09h 11m 23s}  +16.22d {+16d 13' 19"}
SUN_DIST:         94.63 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:      246.67d {+16h 26m 40s}  -22.96d {-22d 57' 44"}
MOON_DIST:       112.34 [deg]
MOON_ILLUM:      70 [%]
GAL_COORDS:      250.57,-50.69 [deg] galactic lon,lat of the burst
ECL_COORDS:       35.45,-61.58 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 0.98 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 08 Aug 11 06:21:27 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     458918,   Seg_Num: 0
GRB_RA:           57.2659d {+03h 49m 03.8s} (J2000),
                  57.3617d {+03h 49m 26.8s} (current),
                  56.8532d {+03h 47m 24.7s} (1950)
GRB_DEC:         -44.1948d {-44d 11' 41.2"} (J2000),
                 -44.1599d {-44d 09' 35.7"} (current),
                 -44.3462d {-44d 20' 46.2"} (1950)
GRB_ERROR:       6.1 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       28 [cnts]
IMG_START_DATE:  15781 TJD;   220 DOY;   11/08/08
IMG_START_TIME:  22845.06 SOD {06:20:45.06} UT,   110.9 [sec] since BAT Trigger Time
CENTROID_X:      312.77,  raw= 313  [pixels]
CENTROID_Y:      271.74,  raw= 272  [pixels]
ROLL:            71.87 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -61.89
GRB_POS_XRT_Z:   21.39
IMAGE_URL:       sw00458918000msxps_rw.img
SUN_POSTN:       137.85d {+09h 11m 23s}  +16.22d {+16d 13' 19"}
SUN_DIST:         94.63 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:      246.67d {+16h 26m 41s}  -22.96d {-22d 57' 45"}
MOON_DIST:       112.34 [deg]
MOON_ILLUM:      70 [%]
GAL_COORDS:      250.57,-50.69 [deg] galactic lon,lat of the burst
ECL_COORDS:       35.45,-61.58 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 08 Aug 11 06:21:34 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     458918,   Seg_Num: 0
GRB_RA:           57.2659d {+03h 49m 03.8s} (J2000),
                  57.3617d {+03h 49m 26.8s} (current),
                  56.8532d {+03h 47m 24.7s} (1950)
GRB_DEC:         -44.1948d {-44d 11' 41.2"} (J2000),
                 -44.1599d {-44d 09' 35.7"} (current),
                 -44.3462d {-44d 20' 46.2"} (1950)
GRB_ERROR:       6.1 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       28 [cnts]
IMG_START_DATE:  15781 TJD;   220 DOY;   11/08/08
IMG_START_TIME:  22845.06 SOD {06:20:45.06} UT,   110.9 [sec] since BAT Trigger Time
CENTROID_X:      312.77,  raw= 313  [pixels]
CENTROID_Y:      271.74,  raw= 272  [pixels]
ROLL:            71.87 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -61.89
GRB_POS_XRT_Z:   21.39
IMAGE_URL:       sw00458918000msxps_rw.img
SUN_POSTN:       137.85d {+09h 11m 23s}  +16.22d {+16d 13' 19"}
SUN_DIST:         94.63 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:      246.67d {+16h 26m 41s}  -22.96d {-22d 57' 45"}
MOON_DIST:       112.34 [deg]
MOON_ILLUM:      70 [%]
GAL_COORDS:      250.57,-50.69 [deg] galactic lon,lat of the burst
ECL_COORDS:       35.45,-61.58 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 08 Aug 11 06:23:05 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     458918,   Seg_Num: 0
GRB_RA:           57.264d {+03h 49m 03s} (J2000),
                  57.360d {+03h 49m 26s} (current),
                  56.851d {+03h 47m 24s} (1950)
GRB_DEC:         -44.179d {-44d 10' 42"} (J2000),
                 -44.144d {-44d 08' 36"} (current),
                 -44.330d {-44d 19' 47"} (1950)
GRB_DATE:        15781 TJD;   220 DOY;   11/08/08
GRB_TIME:        22734.20 SOD {06:18:54.20} UT
TRIGGER_INDEX:   477
GRB_PHI:         170.26 [deg]
GRB_THETA:        29.28 [deg]
DELTA_TIME:      -63.00 [sec]
TRIGGER_DUR:     8.192 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     10.00 [sigma]
IMAGE_SIGNIF:    7.19 [sigma]
LC_URL:          sw00458918000msb.lc
SUN_POSTN:       137.85d {+09h 11m 24s}  +16.22d {+16d 13' 18"}
SUN_DIST:         94.63 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:      246.69d {+16h 26m 45s}  -22.96d {-22d 57' 48"}
MOON_DIST:       112.35 [deg]
MOON_ILLUM:      70 [%]
GAL_COORDS:      250.54,-50.69 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       35.47,-61.56 [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 = 62.92,-19.23 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 08 Aug 11 06:24:07 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     458918,   Seg_Num: 0
POINT_RA:         57.267d {+03h 49m 04s} (J2000)
POINT_DEC:       -44.176d {-44d 10' 34"} (J2000)
POINT_ROLL:      71.869d
IMG_START_DATE:  15781 TJD;   220 DOY;   11/08/08
IMG_START_TIME:  22854.52 SOD {06:20:54.52} UT,   120.3 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.789
N_STARS:         18
X_OFFSET:        464 [pixels]
Y_OFFSET:        560 [pixels]
X_MAX:           1423 [pixels]
Y_MAX:           1519 [pixels]
DET_THRESH:      16
PHOTO_THRESH:    9
SL_URL:          sw00458918000msufc0120.fits
SUN_POSTN:       137.85d {+09h 11m 24s}  +16.22d {+16d 13' 17"}
SUN_DIST:         94.63 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:      246.70d {+16h 26m 47s}  -22.96d {-22d 57' 51"}
MOON_DIST:       112.35 [deg]
MOON_ILLUM:      70 [%]
GAL_COORDS:      250.54,-50.69 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       35.47,-61.56 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 08 Aug 11 06:24:25 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     458918,   Seg_Num: 0
POINT_RA:         57.267d {+03h 49m 04s} (J2000)
POINT_DEC:       -44.176d {-44d 10' 34"} (J2000)
POINT_ROLL:      71.869d
IMG_START_DATE:  15781 TJD;   220 DOY;   11/08/08
IMG_START_TIME:  22854.52 SOD {06:20:54.52} UT,   120.3 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.789
N_STARS:         18
X_OFFSET:        464 [pixels]
Y_OFFSET:        560 [pixels]
X_MAX:           1423 [pixels]
Y_MAX:           1519 [pixels]
DET_THRESH:      16
PHOTO_THRESH:    9
SL_URL:          sw00458918000msufc0120.fits
SUN_POSTN:       137.85d {+09h 11m 24s}  +16.22d {+16d 13' 17"}
SUN_DIST:         94.63 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:      246.70d {+16h 26m 48s}  -22.96d {-22d 57' 51"}
MOON_DIST:       112.35 [deg]
MOON_ILLUM:      70 [%]
GAL_COORDS:      250.54,-50.69 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       35.47,-61.56 [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:     Mon 08 Aug 11 06:25:32 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     458918,   Seg_Num: 0
POINT_RA:         57.267d {+03h 49m 04s} (J2000)
POINT_DEC:       -44.176d {-44d 10' 34"} (J2000)
ROLL:            71.869d
IMG_START_DATE:  15781 TJD;   220 DOY;   11/08/08
IMG_START_TIME:  22854.52 SOD {06:20:54.52} UT,   120.3 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     334477261
X_OFFSET:        812 [pixels]
Y_OFFSET:        989 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       972
Y_GRB_POS:       1149
BINNING_INDEX:   1
IM_URL:          sw00458918000msuni0128.fits
SUN_POSTN:       137.85d {+09h 11m 24s}  +16.22d {+16d 13' 16"}
SUN_DIST:         94.63 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:      246.71d {+16h 26m 51s}  -22.97d {-22d 57' 54"}
MOON_DIST:       112.35 [deg]
MOON_ILLUM:      70 [%]
GAL_COORDS:      250.54,-50.69 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       35.47,-61.56 [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:     Mon 08 Aug 11 06:25:50 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     458918,   Seg_Num: 0
POINT_RA:         57.267d {+03h 49m 04s} (J2000)
POINT_DEC:       -44.176d {-44d 10' 34"} (J2000)
ROLL:            71.869d
IMG_START_DATE:  15781 TJD;   220 DOY;   11/08/08
IMG_START_TIME:  22854.52 SOD {06:20:54.52} UT,   120.3 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     334477261
X_OFFSET:        812 [pixels]
Y_OFFSET:        989 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       972
Y_GRB_POS:       1149
BINNING_INDEX:   1
IM_URL:          sw00458918000msuni0128.fits
SUN_POSTN:       137.85d {+09h 11m 24s}  +16.22d {+16d 13' 16"}
SUN_DIST:         94.63 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:      246.72d {+16h 26m 52s}  -22.97d {-22d 57' 55"}
MOON_DIST:       112.35 [deg]
MOON_ILLUM:      70 [%]
GAL_COORDS:      250.54,-50.69 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       35.47,-61.56 [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:     Mon 08 Aug 11 06:27:01 UT
NOTICE_TYPE:     Swift-UVOT Position
TRIGGER_NUM:     458918,   Seg_Num: 0
GRB_RA:           57.2678d {+03h 49m 04.27s} (J2000),
                  57.3636d {+03h 49m 27.26s} (current),
                  56.8551d {+03h 47m 25.21s} (1950)
GRB_DEC:         -44.1945d {-44d 11' 40.1"} (J2000),
                 -44.1596d {-44d 09' 34.6"} (current),
                 -44.3459d {-44d 20' 45.1"} (1950)
GRB_ERROR:       0.8 [arcsec radius, statistical only]
GRB_MAG:         19.93 +/- 0.19 [mag]
FILTER:          10, White
IMG_START_DATE:  15781 TJD;   220 DOY;   11/08/08
IMG_START_TIME:  22854.00 SOD {06:20:54.00} UT,   119.8 [sec] since BAT Trigger Time
SUN_POSTN:       137.85d {+09h 11m 24s}  +16.22d {+16d 13' 15"}
SUN_DIST:         94.63 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:      246.73d {+16h 26m 55s}  -22.97d {-22d 57' 58"}
MOON_DIST:       112.33 [deg]
MOON_ILLUM:      70 [%]
GAL_COORDS:      250.57,-50.69 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       35.45,-61.58 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT UVOT Position Notice.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        The UVOT position is 4.7 arcsec from the XRT position.  
COMMENTS:        Result based on Genie data.  
COMMENTS:        Notice generated automatically.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 08 Aug 11 06:31:08 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     458918,   Seg_Num: 0
POINT_RA:         57.267d {+03h 49m 04s} (J2000)
POINT_DEC:       -44.179d {-44d 10' 42"} (J2000)
POINT_ROLL:      71.870d
IMG_START_DATE:  15781 TJD;   220 DOY;   11/08/08
IMG_START_TIME:  23012.76 SOD {06:23:32.76} UT,   278.6 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.727
N_STARS:         17
X_OFFSET:        492 [pixels]
Y_OFFSET:        669 [pixels]
X_MAX:           1451 [pixels]
Y_MAX:           1628 [pixels]
DET_THRESH:      11
PHOTO_THRESH:    5
SL_URL:          sw00458918000msufc0278.fits
SUN_POSTN:       137.85d {+09h 11m 25s}  +16.22d {+16d 13' 12"}
SUN_DIST:         94.63 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:      246.77d {+16h 27m 05s}  -22.97d {-22d 58' 07"}
MOON_DIST:       112.34 [deg]
MOON_ILLUM:      70 [%]
GAL_COORDS:      250.54,-50.69 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       35.47,-61.57 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 08 Aug 11 06:31:25 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     458918,   Seg_Num: 0
POINT_RA:         57.267d {+03h 49m 04s} (J2000)
POINT_DEC:       -44.179d {-44d 10' 42"} (J2000)
POINT_ROLL:      71.870d
IMG_START_DATE:  15781 TJD;   220 DOY;   11/08/08
IMG_START_TIME:  23012.76 SOD {06:23:32.76} UT,   278.6 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        1.727
N_STARS:         17
X_OFFSET:        492 [pixels]
Y_OFFSET:        669 [pixels]
X_MAX:           1451 [pixels]
Y_MAX:           1628 [pixels]
DET_THRESH:      11
PHOTO_THRESH:    5
SL_URL:          sw00458918000msufc0278.fits
SUN_POSTN:       137.85d {+09h 11m 25s}  +16.22d {+16d 13' 12"}
SUN_DIST:         94.63 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:      246.77d {+16h 27m 05s}  -22.97d {-22d 58' 08"}
MOON_DIST:       112.34 [deg]
MOON_ILLUM:      70 [%]
GAL_COORDS:      250.54,-50.69 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       35.47,-61.57 [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:     Mon 08 Aug 11 06:32:36 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     458918,   Seg_Num: 0
POINT_RA:         57.267d {+03h 49m 04s} (J2000)
POINT_DEC:       -44.179d {-44d 10' 42"} (J2000)
ROLL:            71.870d
IMG_START_DATE:  15781 TJD;   220 DOY;   11/08/08
IMG_START_TIME:  23012.76 SOD {06:23:32.76} UT,   278.6 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     334477420
X_OFFSET:        812 [pixels]
Y_OFFSET:        989 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       972
Y_GRB_POS:       1149
BINNING_INDEX:   1
IM_URL:          sw00458918000msuni0286.fits
SUN_POSTN:       137.85d {+09h 11m 25s}  +16.22d {+16d 13' 11"}
SUN_DIST:         94.63 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:      246.78d {+16h 27m 08s}  -22.97d {-22d 58' 11"}
MOON_DIST:       112.33 [deg]
MOON_ILLUM:      70 [%]
GAL_COORDS:      250.54,-50.69 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       35.47,-61.57 [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:     Mon 08 Aug 11 06:32:42 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     458918,   Seg_Num: 0
GRB_RA:           57.2665d {+03h 49m 03.96s} (J2000),
                  57.3623d {+03h 49m 26.95s} (current),
                  56.8537d {+03h 47m 24.89s} (1950)
GRB_DEC:         -44.1944d {-44d 11' 39.8"} (J2000),
                 -44.1595d {-44d 09' 34.2"} (current),
                 -44.3458d {-44d 20' 44.8"} (1950)
GRB_ERROR:       2.6 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  15781 TJD;   220 DOY;   11/08/08
IMG_START_TIME:  22927.00 SOD {06:22:07.00} UT,   192.8 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       137.85d {+09h 11m 25s}  +16.22d {+16d 13' 11"}
SUN_DIST:         94.63 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:      246.79d {+16h 27m 09s}  -22.97d {-22d 58' 11"}
MOON_DIST:       112.32 [deg]
MOON_ILLUM:      70 [%]
GAL_COORDS:      250.57,-50.69 [deg] galactic lon,lat of the burst
ECL_COORDS:       35.45,-61.58 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        This is an Update Notice -- the RA,Dec values herein supersede the previous XRT_POS Notice.  
COMMENTS:        TAM values, flux and significance fields are not valid.  
COMMENTS:        This position was automatically generated on the ground using  
COMMENTS:        Photon Counting data telemetered via TDRSS (SPER data).  
COMMENTS:        See http://www.swift.ac.uk/sper/docs.php for details.  
COMMENTS:        This position was enhanced using UVOT field astrometry.  
COMMENTS:        The probability that this is a serendipitous source in the  
COMMENTS:        SPER window is 0.11% < P(seren) < 0.58%.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 08 Aug 11 06:32:55 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     458918,   Seg_Num: 0
POINT_RA:         57.267d {+03h 49m 04s} (J2000)
POINT_DEC:       -44.179d {-44d 10' 42"} (J2000)
ROLL:            71.870d
IMG_START_DATE:  15781 TJD;   220 DOY;   11/08/08
IMG_START_TIME:  23012.76 SOD {06:23:32.76} UT,   278.6 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     334477420
X_OFFSET:        812 [pixels]
Y_OFFSET:        989 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       972
Y_GRB_POS:       1149
BINNING_INDEX:   1
IM_URL:          sw00458918000msuni0286.fits
SUN_POSTN:       137.85d {+09h 11m 25s}  +16.22d {+16d 13' 11"}
SUN_DIST:         94.63 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:      246.79d {+16h 27m 09s}  -22.97d {-22d 58' 11"}
MOON_DIST:       112.33 [deg]
MOON_ILLUM:      70 [%]
GAL_COORDS:      250.54,-50.69 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       35.47,-61.57 [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 #12256
G. Stratta (ASDC), W. H. Baumgartner (GSFC/UMBC), M. M. Chester (PSU), V. D'Elia (ASDC), N. Gehrels (NASA/GSFC), C. Guidorzi (U Ferrara), S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU), A. Melandri (INAF-OAB), K. L. Page (U Leicester) and C. J. Saxton (UCL-MSSL) report on behalf of the Swift Team:
At 06:18:54 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 110808A (trigger=458918). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 57.264, -44.179 which is
```
   RA(J2000) = 03h 49m 03s
   Dec(J2000) = -44d 10' 42"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single-peaked structure with a duration of about 10 sec. The peak count rate was ~400 counts/sec (15-350 keV), at ~4 sec after the trigger.
The XRT began observing the field at 06:20:45.1 UT, 110.9 seconds after the BAT trigger. Using promptly downlinked data we find a bright, fading, uncatalogued X-ray source with an enhanced position: RA, Dec 57.2666, -44.1944 which is equivalent to:
```
   RA(J2000)  = 03h 49m 3.97s
   Dec(J2000) = -44d 11' 40.0"
```
with an uncertainty of 2.6 arcseconds (radius, 90% containment). This location is 55 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 in excess of the Galactic value (1.04 x 10^20 cm^-2, Kalberla et al. 2005), with an excess column of 3 (+3.41/-2.82) x 10^21 cm^-2 (90% confidence).
The initial flux in the 2.5 s image was 5.42e-10 erg cm^-2 s^-1 (0.2-10 keV).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 120 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at
```
  RA(J2000)  =	03:49:04.28 =  57.26782
  DEC(J2000) = -44:11:40.3  = -44.19452
```
with a 90%-confidence error radius of about 0.83 arc sec. This position is 5.1 arc sec. from the center of the XRT error circle. The estimated magnitude is 19.93 with a 1-sigma error of about 0.19. No correction has been made for the expected extinction corresponding to E(B-V) of 0.01.
Burst Advocate for this burst is G. Stratta (giulia.stratta AT asdc.asi.it). Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/too.html.)
GCN Circular #12257
M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team.
Using 304 s of XRT Photon Counting mode data and 1 UVOT images for GRB 110808A, 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 = 57.26664, -44.19536 which is equivalent to:
```
RA (J2000): 03h 49m 3.99s
Dec (J2000): -44d 11' 43.3"
```
with an uncertainty of 3.2 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 #12258
A. de Ugarte Postigo, J. P. U. Fynbo (DARK/NBI), P. Jakobsson (U. Iceland), B. Milvang-Jensen (ESO, DARK/NBI), A. Melandri (INAF-OABr), D. Malesani (DARK/NBI), S. Schulze (U. Iceland), P. Goldoni (APC/Univ. Paris 7 and SAp/CEA), N. R. Tanvir (U. Leicester), H. Flores (Paris Obs.), K. Wiersema (U. Leicester), S. Covino (INAF-OABr), L. Lovisi, B. Lanzoni (U. Bologna) report on behalf of the X-shooter GRB collaboration:
We observed the afterglow of GRB 110808A (Stratta et al. GCN 12256) with the ESO VLT equipped with the X-shooter spectrograph on 8 August 2011, beginning 09:19 UT (3 hr after the GRB). The acquisition image shows the UVOT optical afterglow candidate to have R ~ 21.2 mag.
We detect several emission lines, including [O II], [O III] and H-alpha at a common redshift of z = 1.348 (based on archival calibration frames). At the same redshift we detect the Mg II doublet and Fe transitions in absorption.
We acknowledge the support of the VLT staff, in particular Claudio Melo.
GCN Circular #12261
G. Stratta and V. D'Elia (ASDC) report on behalf of the Swift-XRT team:
We have analysed 3.8 ks of XRT data for GRB 110808A (Stratta et al. GCN Circ. 12256), from 100 s to 18.0 ks after the BAT trigger. The data comprise 91 s in Windowed Timing (WT) mode (the first 9 s were taken while Swift was slewing) with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Goad et al. (GCN. Circ 12257).
The light curve can be modelled with an initial power-law decay with an index of alpha=3.79 (+0.22, -0.20), followed by a break at T+459 s to an alpha of 0.57 (+0.18, -0.23).
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 3.07 (+0.29, -0.25). The best-fitting absorption column is 2.9 (+1.4, -1.3) x 10^21 cm^-2, at a redshift of 1.348 (de Ugarte Postigo et al. GCN Circ. 12258), in addition to the Galactic value of 1.0 x 10^20 cm^-2 (Kalberla et al. 2005). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 2.2 x 10^-11 (3.5 x 10^-11) erg cm^-2 count^-1.
A summary of the WT-mode spectrum is thus:
```
Galactic foreground: 1.0 x 10^20 cm^-2
Intrinsic column:    2.9 (+1.4, -1.3) x 10^21 cm^-2 at z=1.348
Photon index:	     3.07 (+0.29, -0.25)
```
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00458918.
This circular is an official product of the Swift-XRT team.
GCN Circular #12262
T. Sakamoto (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), D. M. Palmer (LANL), G. Sato (ISAS), M. Stamatikos (OSU), G. Stratta (ASDC), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team):
Using the data set from T-471 to T+639 sec from recent telemetry downlinks, we report further analysis of BAT GRB 110808A (trigger #458918) (Stratta, et al., GCN Circ. 12256). The BAT ground-calculated position is RA, Dec = 57.322, -44.177 deg which is
```
   RA(J2000)  =  03h 49m 17.2s 
   Dec(J2000) = -44d 10' 35.4" 
```
with an uncertainty of 2.7 arcmin, (radius, sys+stat, 90% containment). The partial coding was 76%.
The mask-weighted light curve shows a FRED pulse shape starting at ~T+0 sec, peaking at ~T+1 sec, and returning the baseline at ~T+50 sec. T90 (15-350 keV) is 48 +- 23 sec (estimated error including systematics).
The time-averaged spectrum from T-7.4 to T+40.6 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.32 +- 0.43. The fluence in the 15-150 keV band is 3.3 +- 0.8 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+0.06 sec in the 15-150 keV band is 0.4 +- 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/458918/BA/

GCN Circular #12264
T. A. Pritchard (PSU) and G. Stratta (ASDC) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 110808A 120 s after the BAT trigger (Stratta et al., GCN Circ. 12256). A source consistent with the Enhanced Swift-XRT position (Goad et al., GCN Circ. 12257) is detected in the initial UVOT exposures.
The preliminary UVOT position is:

     RA  (J2000) =3D  03:49:04.27 =3D  57.26780 (deg.)
     Dec (J2000) =3D -44:11:40.1  =3D -44.19448 (deg.)

with an estimated uncertainty of 0.64 arc sec. (radius, 90% confidence).
Preliminary detections and 3-sigma upper limits using the UVOT=20 photometric system (Poole et al. 2008, MNRAS, 383, 627) for the early exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)           Mag

white              120          270          147         19.88 =B1 0.14
white              57           559           19         18.48 =B1 0.23
white              3996         4196         200         20.17 =B1 0.16
v                  609          629           19 >18.7
b                  535          555           20         18.64 =B1 0.32
u                  279          528          246         18.28 =B1 0.09
u                  683          703           19         17.48 =B1 0.25
u                  6062         6262         196 >20.62
w1                 658          678           19 >17.8
w2                 585          605           19 >18.3

The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) =3D 0.01 in the direction of the burst (Schlegel et al. 1998).

GCN Circular #12270
S. Golenetskii, R.Aptekar, D. Frederiks, E. Mazets, V. Pal'shin, P. Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind team, report:
The short-duration extremely hard GRB 110808A (localized by IPN: Hurley et al., GCN 12269) triggered Konus-Wind at T0=3D56695.237s UT (15:44:55.237)
The burst light curve shows a single bright hard pulse, with a duration of ~0.5 s and much weaker tail of the emission which is detectable till T0+8 s. The emission is seen up to 13 MeV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB110808_T56695/
As observed by Konus-Wind the burst had a fluence of (1.6 =B1 0.2)x10-5 erg/cm2, and a 16-ms peak flux, measured from T0+0.112 s, of (1.1 =B1 0.2)x10-4 erg/cm2/s (both in the 20 keV - 10 MeV energy range).
The spectrum of the burst (measured from T0 to T0+0.256 s) is best fitted in the 20 keV - 10 MeV range by a power law with exponential cutoff model, for which alpha =3D -1.13 (-0.08, +0.08), and Ep =3D 2960(-796, +1217) keV, chi2 =3D 53.2/45 dof. Fitting this spectrum by the GRB (Band) function yields the following model parameters:
```
the low-energy photon index alpha =3D -1.13 (-0.08, +0.07),
the high energy photon index beta =3D -2.5 (<-1.9),
the peak energy Ep =3D 2630(-744, +836) keV,
chi2 =3D 54.3/44 dof.
```
The spectrum at the maximum count rate (measured from T0+0.064 to T0+0.128 s) is best fitted in the 20 keV - 10 MeV range by a power law with exponential cutoff model, for which alpha =3D -1.07 (-0.11, +0.12), and Ep =3D 4238(-1530, +3270) keV, chi2 =3D 12.5/16 dof.
All the quoted results are preliminary. All the quoted errors are at the 90% confidence level.
GCN Report 341.1
GCN_Report 341.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_341_1.pdf by G. Stratta at ASDC titled: "Final Swift observations of GRB 110808A"

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Jochen Greiner, last update: 11-Aug-2011 [Disclaimer]