Gamma-ray Burst 170804A

(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 04 Aug 17 12:02:40 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     766194,   Seg_Num: 0
GRB_RA:            6.433d {+00h 25m 44s} (J2000),
                   6.635d {+00h 26m 32s} (current),
                   5.856d {+00h 23m 25s} (1950)
GRB_DEC:         -64.748d {-64d 44' 52"} (J2000),
                 -64.651d {-64d 39' 02"} (current),
                 -65.025d {-65d 01' 29"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       38571 [cnts]    Image_Peak=681 [image_cnts]
TRIGGER_DUR:     12.160 [sec] 
TRIGGER_INDEX:   478     E_range: 25-100 keV
BKG_INTEN:       184731 [cnts]
BKG_TIME:        43204.52 SOD {12:00:04.52} UT
BKG_DUR:         64 [sec]
GRB_DATE:        17969 TJD;   216 DOY;   17/08/04
GRB_TIME:        43297.38 SOD {12:01:37.38} UT
GRB_PHI:         -24.62 [deg]
GRB_THETA:        32.38 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     10.00 [sigma]
IMAGE_SIGNIF:    8.82 [sigma]
MERIT_PARAMS:     +1  +0  +0  +4  +2  -1  +0  +0 +52  +0 
SUN_POSTN:       134.77d {+08h 59m 05s}  +17.11d {+17d 06' 23"}
SUN_DIST:        121.23 [deg]   Sun_angle= 8.5 [hr] (West of Sun)
MOON_POSTN:      276.09d {+18h 24m 23s}  -19.32d {-19d 18' 56"}
MOON_DIST:        72.84 [deg]
MOON_ILLUM:      90 [%]
GAL_COORDS:      307.40,-52.16 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      323.31,-58.08 [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 = 193.95,3.24 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 04 Aug 17 12:04:05 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     766194,   Seg_Num: 0
GRB_RA:            6.3904d {+00h 25m 33.69s} (J2000),
                   6.5923d {+00h 26m 22.16s} (current),
                   5.8131d {+00h 23m 15.14s} (1950)
GRB_DEC:         -64.7802d {-64d 46' 48.7"} (J2000),
                 -64.6829d {-64d 40' 58.4"} (current),
                 -65.0570d {-65d 03' 25.2"} (1950)
GRB_ERROR:       6.3 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       5.37e-10 [erg/cm2/sec]
GRB_SIGNIF:      5.38 [sigma]
IMG_START_DATE:  17969 TJD;   216 DOY;   17/08/04
IMG_START_TIME:  43419.97 SOD {12:03:39.97} UT,   122.6 [sec] since BAT Trigger Time
TAM[0-3]:        327.65 237.23 261.66 243.71
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       134.77d {+08h 59m 05s}  +17.11d {+17d 06' 22"}
SUN_DIST:        121.23 [deg]   Sun_angle= 8.5 [hr] (West of Sun)
MOON_POSTN:      276.11d {+18h 24m 26s}  -19.32d {-19d 18' 57"}
MOON_DIST:        72.81 [deg]
MOON_ILLUM:      90 [%]
GAL_COORDS:      307.42,-52.12 [deg] galactic lon,lat of the burst
ECL_COORDS:      323.24,-58.09 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 2.21 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 04 Aug 17 12:04:17 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     766194,   Seg_Num: 0
GRB_RA:            6.3904d {+00h 25m 33.6s} (J2000),
                   6.5923d {+00h 26m 22.1s} (current),
                   5.8131d {+00h 23m 15.1s} (1950)
GRB_DEC:         -64.7802d {-64d 46' 48.7"} (J2000),
                 -64.6829d {-64d 40' 58.4"} (current),
                 -65.0570d {-65d 03' 25.2"} (1950)
GRB_ERROR:       6.1 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       29 [cnts]
IMG_START_DATE:  17969 TJD;   216 DOY;   17/08/04
IMG_START_TIME:  43419.97 SOD {12:03:39.97} UT,   122.6 [sec] since BAT Trigger Time
CENTROID_X:      288.32,  raw= 288  [pixels]
CENTROID_Y:      241.90,  raw= 242  [pixels]
ROLL:            118.74 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -133.16
GRB_POS_XRT_Z:   -42.60
IMAGE_URL:       sw00766194000msxps_rw.img
SUN_POSTN:       134.77d {+08h 59m 05s}  +17.11d {+17d 06' 22"}
SUN_DIST:        121.23 [deg]   Sun_angle= 8.5 [hr] (West of Sun)
MOON_POSTN:      276.11d {+18h 24m 26s}  -19.32d {-19d 18' 57"}
MOON_DIST:        72.81 [deg]
MOON_ILLUM:      90 [%]
GAL_COORDS:      307.42,-52.12 [deg] galactic lon,lat of the burst
ECL_COORDS:      323.24,-58.09 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 04 Aug 17 12:04:15 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     766194,   Seg_Num: 0
GRB_RA:            6.3904d {+00h 25m 33.6s} (J2000),
                   6.5923d {+00h 26m 22.1s} (current),
                   5.8131d {+00h 23m 15.1s} (1950)
GRB_DEC:         -64.7802d {-64d 46' 48.7"} (J2000),
                 -64.6829d {-64d 40' 58.4"} (current),
                 -65.0570d {-65d 03' 25.2"} (1950)
GRB_ERROR:       6.1 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       29 [cnts]
IMG_START_DATE:  17969 TJD;   216 DOY;   17/08/04
IMG_START_TIME:  43419.97 SOD {12:03:39.97} UT,   122.6 [sec] since BAT Trigger Time
CENTROID_X:      288.32,  raw= 288  [pixels]
CENTROID_Y:      241.90,  raw= 242  [pixels]
ROLL:            118.74 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -133.16
GRB_POS_XRT_Z:   -42.60
IMAGE_URL:       sw00766194000msxps_rw.img
SUN_POSTN:       134.77d {+08h 59m 05s}  +17.11d {+17d 06' 22"}
SUN_DIST:        121.23 [deg]   Sun_angle= 8.5 [hr] (West of Sun)
MOON_POSTN:      276.11d {+18h 24m 26s}  -19.32d {-19d 18' 57"}
MOON_DIST:        72.81 [deg]
MOON_ILLUM:      90 [%]
GAL_COORDS:      307.42,-52.12 [deg] galactic lon,lat of the burst
ECL_COORDS:      323.24,-58.09 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 04 Aug 17 12:05:41 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     766194,   Seg_Num: 0
GRB_RA:            6.433d {+00h 25m 44s} (J2000),
                   6.635d {+00h 26m 32s} (current),
                   5.856d {+00h 23m 25s} (1950)
GRB_DEC:         -64.748d {-64d 44' 52"} (J2000),
                 -64.651d {-64d 39' 02"} (current),
                 -65.025d {-65d 01' 29"} (1950)
GRB_DATE:        17969 TJD;   216 DOY;   17/08/04
GRB_TIME:        43297.38 SOD {12:01:37.38} UT
TRIGGER_INDEX:   478
GRB_PHI:         -24.62 [deg]
GRB_THETA:        32.38 [deg]
DELTA_TIME:      -5.00 [sec]
TRIGGER_DUR:     12.160 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     10.00 [sigma]
IMAGE_SIGNIF:    8.82 [sigma]
LC_URL:          sw00766194000msb.lc
SUN_POSTN:       134.77d {+08h 59m 05s}  +17.11d {+17d 06' 21"}
SUN_DIST:        121.23 [deg]   Sun_angle= 8.5 [hr] (West of Sun)
MOON_POSTN:      276.12d {+18h 24m 29s}  -19.32d {-19d 18' 58"}
MOON_DIST:        72.82 [deg]
MOON_ILLUM:      90 [%]
GAL_COORDS:      307.40,-52.16 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      323.31,-58.08 [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 = 193.95,3.24 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 04 Aug 17 12:06:56 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     766194,   Seg_Num: 0
POINT_RA:          6.408d {+00h 25m 38s} (J2000)
POINT_DEC:       -64.743d {-64d 44' 33"} (J2000)
POINT_ROLL:      118.735d
IMG_START_DATE:  17969 TJD;   216 DOY;   17/08/04
IMG_START_TIME:  43428.92 SOD {12:03:48.92} UT,   131.5 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.382
N_STARS:         52
X_OFFSET:        568 [pixels]
Y_OFFSET:        520 [pixels]
X_MAX:           1527 [pixels]
Y_MAX:           1479 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00766194000msufc0131.fits
SUN_POSTN:       134.77d {+08h 59m 05s}  +17.11d {+17d 06' 20"}
SUN_DIST:        121.24 [deg]   Sun_angle= 8.5 [hr] (West of Sun)
MOON_POSTN:      276.13d {+18h 24m 32s}  -19.32d {-19d 18' 59"}
MOON_DIST:        72.81 [deg]
MOON_ILLUM:      90 [%]
GAL_COORDS:      307.41,-52.16 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      323.30,-58.07 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 04 Aug 17 12:07:07 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     766194,   Seg_Num: 0
POINT_RA:          6.408d {+00h 25m 38s} (J2000)
POINT_DEC:       -64.743d {-64d 44' 33"} (J2000)
POINT_ROLL:      118.735d
IMG_START_DATE:  17969 TJD;   216 DOY;   17/08/04
IMG_START_TIME:  43428.92 SOD {12:03:48.92} UT,   131.5 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.382
N_STARS:         52
X_OFFSET:        568 [pixels]
Y_OFFSET:        520 [pixels]
X_MAX:           1527 [pixels]
Y_MAX:           1479 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00766194000msufc0131.fits
SUN_POSTN:       134.77d {+08h 59m 05s}  +17.11d {+17d 06' 20"}
SUN_DIST:        121.24 [deg]   Sun_angle= 8.5 [hr] (West of Sun)
MOON_POSTN:      276.13d {+18h 24m 32s}  -19.32d {-19d 18' 59"}
MOON_DIST:        72.81 [deg]
MOON_ILLUM:      90 [%]
GAL_COORDS:      307.41,-52.16 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      323.30,-58.07 [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 04 Aug 17 12:08:11 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     766194,   Seg_Num: 0
POINT_RA:          6.408d {+00h 25m 38s} (J2000)
POINT_DEC:       -64.743d {-64d 44' 33"} (J2000)
ROLL:            118.735d
IMG_START_DATE:  17969 TJD;   216 DOY;   17/08/04
IMG_START_TIME:  43428.92 SOD {12:03:48.92} UT,   131.5 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     523541048
X_OFFSET:        1011 [pixels]
Y_OFFSET:        1074 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1171
Y_GRB_POS:       1234
BINNING_INDEX:   1
IM_URL:          sw00766194000msuni0151.fits
SUN_POSTN:       134.77d {+08h 59m 06s}  +17.11d {+17d 06' 20"}
SUN_DIST:        121.24 [deg]   Sun_angle= 8.5 [hr] (West of Sun)
MOON_POSTN:      276.14d {+18h 24m 34s}  -19.32d {-19d 19' 00"}
MOON_DIST:        72.80 [deg]
MOON_ILLUM:      90 [%]
GAL_COORDS:      307.41,-52.16 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      323.30,-58.07 [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 04 Aug 17 12:08:23 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     766194,   Seg_Num: 0
POINT_RA:          6.408d {+00h 25m 38s} (J2000)
POINT_DEC:       -64.743d {-64d 44' 33"} (J2000)
ROLL:            118.735d
IMG_START_DATE:  17969 TJD;   216 DOY;   17/08/04
IMG_START_TIME:  43428.92 SOD {12:03:48.92} UT,   131.5 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     523541048
X_OFFSET:        1011 [pixels]
Y_OFFSET:        1074 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1171
Y_GRB_POS:       1234
BINNING_INDEX:   1
IM_URL:          sw00766194000msuni0151.fits
SUN_POSTN:       134.77d {+08h 59m 06s}  +17.11d {+17d 06' 20"}
SUN_DIST:        121.24 [deg]   Sun_angle= 8.5 [hr] (West of Sun)
MOON_POSTN:      276.14d {+18h 24m 35s}  -19.32d {-19d 19' 00"}
MOON_DIST:        72.80 [deg]
MOON_ILLUM:      90 [%]
GAL_COORDS:      307.41,-52.16 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      323.30,-58.07 [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 04 Aug 17 12:10:10 UT
NOTICE_TYPE:     Swift-UVOT Position
TRIGGER_NUM:     766194,   Seg_Num: 0
GRB_RA:            6.3935d {+00h 25m 34.44s} (J2000),
                   6.5954d {+00h 26m 22.90s} (current),
                   5.8163d {+00h 23m 15.90s} (1950)
GRB_DEC:         -64.7841d {-64d 47' 02.7"} (J2000),
                 -64.6868d {-64d 41' 12.4"} (current),
                 -65.0609d {-65d 03' 39.3"} (1950)
GRB_ERROR:       0.6 [arcsec radius, statistical only]
GRB_MAG:         19.01 +/- 0.14 [mag]
FILTER:          10, White
IMG_START_DATE:  17969 TJD;   216 DOY;   17/08/04
IMG_START_TIME:  43425.00 SOD {12:03:45.00} UT,   127.6 [sec] since BAT Trigger Time
SUN_POSTN:       134.77d {+08h 59m 06s}  +17.11d {+17d 06' 18"}
SUN_DIST:        121.23 [deg]   Sun_angle= 8.5 [hr] (West of Sun)
MOON_POSTN:      276.16d {+18h 24m 38s}  -19.32d {-19d 19' 00"}
MOON_DIST:        72.78 [deg]
MOON_ILLUM:      90 [%]
GAL_COORDS:      307.41,-52.12 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      323.23,-58.09 [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 14.4 arcsec from the XRT position.  
COMMENTS:        Result based on Genie data.  
COMMENTS:        Notice generated automatically.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 04 Aug 17 12:13:54 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     766194,   Seg_Num: 0
POINT_RA:          6.408d {+00h 25m 38s} (J2000)
POINT_DEC:       -64.740d {-64d 44' 24"} (J2000)
POINT_ROLL:      118.735d
IMG_START_DATE:  17969 TJD;   216 DOY;   17/08/04
IMG_START_TIME:  43586.84 SOD {12:06:26.84} UT,   289.5 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.484
N_STARS:         190
X_OFFSET:        691 [pixels]
Y_OFFSET:        754 [pixels]
X_MAX:           1650 [pixels]
Y_MAX:           1713 [pixels]
DET_THRESH:      6
PHOTO_THRESH:    3
SL_URL:          sw00766194000msufc0289.fits
SUN_POSTN:       134.78d {+08h 59m 07s}  +17.10d {+17d 06' 16"}
SUN_DIST:        121.25 [deg]   Sun_angle= 8.5 [hr] (West of Sun)
MOON_POSTN:      276.19d {+18h 24m 46s}  -19.32d {-19d 19' 02"}
MOON_DIST:        72.78 [deg]
MOON_ILLUM:      90 [%]
GAL_COORDS:      307.42,-52.16 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      323.30,-58.07 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 04 Aug 17 12:14:05 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     766194,   Seg_Num: 0
POINT_RA:          6.408d {+00h 25m 38s} (J2000)
POINT_DEC:       -64.740d {-64d 44' 24"} (J2000)
POINT_ROLL:      118.735d
IMG_START_DATE:  17969 TJD;   216 DOY;   17/08/04
IMG_START_TIME:  43586.84 SOD {12:06:26.84} UT,   289.5 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.484
N_STARS:         190
X_OFFSET:        691 [pixels]
Y_OFFSET:        754 [pixels]
X_MAX:           1650 [pixels]
Y_MAX:           1713 [pixels]
DET_THRESH:      6
PHOTO_THRESH:    3
SL_URL:          sw00766194000msufc0289.fits
SUN_POSTN:       134.78d {+08h 59m 07s}  +17.10d {+17d 06' 16"}
SUN_DIST:        121.25 [deg]   Sun_angle= 8.5 [hr] (West of Sun)
MOON_POSTN:      276.19d {+18h 24m 47s}  -19.32d {-19d 19' 02"}
MOON_DIST:        72.78 [deg]
MOON_ILLUM:      90 [%]
GAL_COORDS:      307.42,-52.16 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      323.30,-58.07 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        If you have elected to receive attachments:  
COMMENTS:        The uvot_catalog_srclist.fits.gz file does not exist; skipping the attachment.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 04 Aug 17 12:15:02 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     766194,   Seg_Num: 0
POINT_RA:          6.408d {+00h 25m 38s} (J2000)
POINT_DEC:       -64.740d {-64d 44' 24"} (J2000)
ROLL:            118.735d
IMG_START_DATE:  17969 TJD;   216 DOY;   17/08/04
IMG_START_TIME:  43586.84 SOD {12:06:26.84} UT,   289.5 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     523541206
X_OFFSET:        1011 [pixels]
Y_OFFSET:        1074 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1171
Y_GRB_POS:       1234
BINNING_INDEX:   1
IM_URL:          sw00766194000msuni0309.fits
SUN_POSTN:       134.78d {+08h 59m 07s}  +17.10d {+17d 06' 15"}
SUN_DIST:        121.25 [deg]   Sun_angle= 8.5 [hr] (West of Sun)
MOON_POSTN:      276.20d {+18h 24m 49s}  -19.32d {-19d 19' 03"}
MOON_DIST:        72.78 [deg]
MOON_ILLUM:      90 [%]
GAL_COORDS:      307.42,-52.16 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      323.30,-58.07 [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 04 Aug 17 12:15:12 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     766194,   Seg_Num: 0
POINT_RA:          6.408d {+00h 25m 38s} (J2000)
POINT_DEC:       -64.740d {-64d 44' 24"} (J2000)
ROLL:            118.735d
IMG_START_DATE:  17969 TJD;   216 DOY;   17/08/04
IMG_START_TIME:  43586.84 SOD {12:06:26.84} UT,   289.5 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     523541206
X_OFFSET:        1011 [pixels]
Y_OFFSET:        1074 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1171
Y_GRB_POS:       1234
BINNING_INDEX:   1
IM_URL:          sw00766194000msuni0309.fits
SUN_POSTN:       134.78d {+08h 59m 07s}  +17.10d {+17d 06' 15"}
SUN_DIST:        121.25 [deg]   Sun_angle= 8.5 [hr] (West of Sun)
MOON_POSTN:      276.20d {+18h 24m 49s}  -19.32d {-19d 19' 03"}
MOON_DIST:        72.78 [deg]
MOON_ILLUM:      90 [%]
GAL_COORDS:      307.42,-52.16 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      323.30,-58.07 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        If you have elected to receive attachments:  
COMMENTS:        The uvot_catalog_image.fits.gz file does not exist; skipping the attachment.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 04 Aug 17 12:19:23 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     766194,   Seg_Num: 0
POINT_RA:          6.408d {+00h 25m 38s} (J2000)
POINT_DEC:       -64.740d {-64d 44' 24"} (J2000)
POINT_ROLL:      118.735d
IMG_START_DATE:  17969 TJD;   216 DOY;   17/08/04
IMG_START_TIME:  44167.96 SOD {12:16:07.96} UT,   870.6 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.433
N_STARS:         190
X_OFFSET:        451 [pixels]
Y_OFFSET:        514 [pixels]
X_MAX:           1890 [pixels]
Y_MAX:           1953 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00766194000msufc0870.fits
SUN_POSTN:       134.78d {+08h 59m 07s}  +17.10d {+17d 06' 12"}
SUN_DIST:        121.25 [deg]   Sun_angle= 8.5 [hr] (West of Sun)
MOON_POSTN:      276.24d {+18h 24m 58s}  -19.32d {-19d 19' 05"}
MOON_DIST:        72.76 [deg]
MOON_ILLUM:      90 [%]
GAL_COORDS:      307.41,-52.16 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      323.30,-58.07 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 04 Aug 17 12:19:39 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     766194,   Seg_Num: 0
POINT_RA:          6.408d {+00h 25m 38s} (J2000)
POINT_DEC:       -64.740d {-64d 44' 24"} (J2000)
POINT_ROLL:      118.735d
IMG_START_DATE:  17969 TJD;   216 DOY;   17/08/04
IMG_START_TIME:  44167.96 SOD {12:16:07.96} UT,   870.6 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.433
N_STARS:         190
X_OFFSET:        451 [pixels]
Y_OFFSET:        514 [pixels]
X_MAX:           1890 [pixels]
Y_MAX:           1953 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00766194000msufc0870.fits
SUN_POSTN:       134.78d {+08h 59m 07s}  +17.10d {+17d 06' 12"}
SUN_DIST:        121.25 [deg]   Sun_angle= 8.5 [hr] (West of Sun)
MOON_POSTN:      276.24d {+18h 24m 58s}  -19.32d {-19d 19' 05"}
MOON_DIST:        72.76 [deg]
MOON_ILLUM:      90 [%]
GAL_COORDS:      307.41,-52.16 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      323.30,-58.07 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        If you have elected to receive attachments:  
COMMENTS:        The uvot_catalog_srclist.fits.gz file does not exist; skipping the attachment.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 04 Aug 17 12:20:10 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     766194,   Seg_Num: 0
GRB_RA:            6.3928d {+00h 25m 34.27s} (J2000),
                   6.5947d {+00h 26m 22.73s} (current),
                   5.8156d {+00h 23m 15.73s} (1950)
GRB_DEC:         -64.7840d {-64d 47' 02.4"} (J2000),
                 -64.6867d {-64d 41' 12.1"} (current),
                 -65.0608d {-65d 03' 38.9"} (1950)
GRB_ERROR:       2.1 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  17969 TJD;   216 DOY;   17/08/04
IMG_START_TIME:  43538.00 SOD {12:05:38.00} UT,   240.6 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       134.78d {+08h 59m 08s}  +17.10d {+17d 06' 12"}
SUN_DIST:        121.23 [deg]   Sun_angle= 8.5 [hr] (West of Sun)
MOON_POSTN:      276.25d {+18h 25m 00s}  -19.32d {-19d 19' 05"}
MOON_DIST:        72.75 [deg]
MOON_ILLUM:      90 [%]
GAL_COORDS:      307.41,-52.12 [deg] galactic lon,lat of the burst
ECL_COORDS:      323.23,-58.09 [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 Circular #21410
A. Cholden-Brown (PSU), D. N. Burrows (PSU), P. A. Evans (U Leicester), J. A. Kennea (PSU), S. J. LaPorte (PSU), A. Y. Lien (GSFC/UMBC), F. E. Marshall (NASA/GSFC), K. L. Page (U Leicester) and B. Sbarufatti (INAF-OAB/PSU) report on behalf of the Swift Team:
At 12:01:37 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 170804A (trigger=766194). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 6.433, -64.748 which is
```
   RA(J2000) = 00h 25m 44s
   Dec(J2000) = -64d 44' 52"
```
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 40 sec. The peak count rate was ~1400 counts/sec (15-350 keV), at ~5 sec after the trigger.
The XRT began observing the field at 12:03:39.9 UT, 122.6 seconds after the BAT trigger. Using promptly downlinked data we find a bright, uncatalogued X-ray source located at RA, Dec 6.39106, -64.78341 which is equivalent to:
```
   RA(J2000)  = 00h 25m 33.85s
   Dec(J2000) = -64d 47' 00.3"
```
with an uncertainty of 3.7 arcseconds (radius, 90% containment). This location is 142 arcseconds from the BAT onboard position, within the BAT error circle. This position may be improved as more data are received; the latest position is available at http://www.swift.ac.uk/sper. We cannot determine whether the source is fading at the present time.
A power-law fit to a spectrum formed from promptly downlinked event data gives a column density in excess of the Galactic value (1.79 x 10^20 cm^-2, Willingale et al. 2013), with an excess column of 2.4 (+3.30/-2.37) x 10^21 cm^-2 (90% confidence).
The initial flux in the 2.5 s image was 5.37e-10 erg cm^-2 s^-1 (0.2-10 keV).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 131 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at
```
  RA(J2000)  =	00:25:34.45 =	6.39354
  DEC(J2000) = -64:47:03.0  = -64.78416
```
with a 90%-confidence error radius of about 0.63 arc sec. This position is 6.9 arc sec. from the center of the XRT error circle. The estimated magnitude is 19.01 with a 1-sigma error of about 0.15. No correction has been made for the expected extinction corresponding to E(B-V) of 0.02.
Burst Advocate for this burst is A. Cholden-Brown (aaronb AT swift.psu.edu). 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 #21413
P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team.
Using 1208 s of XRT Photon Counting mode data and 2 UVOT images for GRB 170804A, 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 = 6.39233, -64.78429 which is equivalent to:
```
RA (J2000): 00h 25m 34.16s
Dec (J2000): -64d 47' 03.4"
```
with an uncertainty of 1.8 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 #21414
D.N. Burrows (PSU), K.L. Page (U. Leicester), B. Mingo (U. Leicester), A.P. Beardmore (U. Leicester), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), A. D'Ai (INAF-IASFPA), S. J. LaPorte (PSU) and A. Cholden-Brown report on behalf of the Swift-XRT team:
We have analysed 6.5 ks of XRT data for GRB 170804A (Cholden-Brown et al. GCN Circ. 21410), from 112 s to 19.6 ks after the BAT trigger. The data comprise 95 s in Windowed Timing (WT) mode (the first 8 s were taken while Swift was slewing) with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Evans et al. (GCN Circ. 21413).
The light curve can be modelled with an initial power-law decay with an index of alpha=2.90 (+0.34, -0.22), followed by a break at T+519 s to an alpha of 1.13 (+0.20, -0.13).
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 2.37 (+0.16, -0.13). The best-fitting absorption column is consistent with the Galactic value of 1.8 x 10^20 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 1.97 (+0.16, -0.14) and a best-fitting absorption column consistent with the Galactic value. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.2 x 10^-11 (3.4 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     1.8 (+2.4, -0.0) x 10^20 cm^-2
Galactic foreground: 1.8 x 10^20 cm^-2
Excess significance: <1.6 sigma
Photon index:	     1.97 (+0.16, -0.14)
```
If the light curve continues to decay with a power-law decay index of 1.13, the count rate at T+24 hours will be 8.3 x 10^-4 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.7 x 10^-14 (2.8 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/00766194.
This circular is an official product of the Swift-XRT team.
GCN Circular #21415
S. R. Oates (U. Warwick) and A. Cholden-Brown (PSU) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 170804A 132 s after the BAT trigger (Cholden-Brown et al., GCN Circ. 21410).
A fading source consistent with the XRT position (Evans et al., GCN Circ. 21413) is detected in the initial UVOT exposures.
The preliminary UVOT position is:
```
     RA  (J2000) =   0:25:34.29 =   6.39288 (deg.)
     Dec (J2000) = -64:47:03.1  = -64.78419 (deg.)
```
with an estimated uncertainty of 0.5 arc sec. (radius, 90% confidence).
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         132          281           147         18.9 +/- 0.1
white            871          1020          147         20.0 +/- 0.2
u_FC             289          539           246         18.7 +/- 0.1
v         796          1243           58         >18.7
b                545          565            19         18.9 +/- 0.4
uvw1             671          1292           78         >19.0
uvw2             596          1392           97         >19.2
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.02 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #21416
H. A. Krimm (NSF/USRA), S. D. Barthelmy (GSFC), A. Cholden-Brown (PSU), J. R. Cummings (CPI), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):
Using the data set from T-240 to T+962 sec from the recent telemetry downlink, we report further analysis of BAT GRB 170804A (trigger #766194) (Cholden-Brown et al., GCN Circ. 21410). The BAT ground-calculated position is RA, Dec = 6.404, -64.781 deg which is
```
  RA(J2000)  =  00h 25m 37.0s
  Dec(J2000) = -64d 46' 50.9"
```
with an uncertainty of 1.3 arcmin, (radius, sys+stat, 90% containment). The partial coding was 75%.
The mask-weighted light curve shows several over-lapping pulses that start at ~T0 and end at ~T+60 s. T90 (15-350 keV) is 43.4 +- 9.8 sec (estimated error including systematics).
The time-averaged spectrum from T+1.98 to T+60.90 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.67 +- 0.13. The fluence in the 15-150 keV band is 1.3 +- 0.1 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+25.10 sec in the 15-150 keV band is 0.9 +- 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/766194/BA/
GCN Circular #21417
A. Cucchiara, D. Morris (U. of the Virgin Islands), and N. Orange (OrangeWave), report on behalf of a larger collaboration:
"On August 4.79 UT (T_0 +7.0h) we began observing the center of the field of GRB 170804A (Cholden-Brown et al. GCN 21410, Emery et al. GCN 21411) using the Las Cumbres Observatory 1m telescope located in Siding Spring Observatory.
Under poor sky conditions (seeing ~2.6 arcseconds) we performed a series of 5x240s observations in SDSS r' and i=E2=80=99 bands for a total of 20 minutes on sky in each filter at average airmass of 1.3.
In the full median stacked images we identified no optical counterpart within the center of the Swift-XRT refined position or at the UVOT optical counterpart location (Evans et al. GCN 21413, Emery et al. GCN 21411) at the following 3-sigma limits:
```
r' > 21.4 mag
i' > 21.1 mag
```
These magnitudes are calibrated against nearby USNO-B1 sources, converted in SDSS bands, and not corrected for Galactic extinction."

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Jochen Greiner, last update: 08-Aug-2017 [Disclaimer]