Gamma-ray Burst 180805B

(All information courtesy of the instrument teams.)

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Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 05 Aug 18 13:02:54 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     851855,   Seg_Num: 0
GRB_RA:           25.813d {+01h 43m 15s} (J2000),
                  26.037d {+01h 44m 09s} (current),
                  25.211d {+01h 40m 51s} (1950)
GRB_DEC:         -17.503d {-17d 30' 11"} (J2000),
                 -17.410d {-17d 24' 36"} (current),
                 -17.755d {-17d 45' 15"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       1215 [cnts]    Image_Peak=127 [image_cnts]
TRIGGER_DUR:     0.256 [sec] 
TRIGGER_INDEX:   481     E_range: 50-350 keV
BKG_INTEN:       17063 [cnts]
BKG_TIME:        46946.62 SOD {13:02:26.62} UT
BKG_DUR:         8 [sec]
GRB_DATE:        18335 TJD;   217 DOY;   18/08/05
GRB_TIME:        46956.47 SOD {13:02:36.47} UT
GRB_PHI:         -42.05 [deg]
GRB_THETA:        28.71 [deg]
SOLN_STATUS:     0x20000003
RATE_SIGNIF:     27.98 [sigma]
IMAGE_SIGNIF:    10.44 [sigma]
MERIT_PARAMS:     +1  +0  +0  -2  +3  +0  +0  +0 +39  +0 
SUN_POSTN:       135.54d {+09h 02m 09s}  +16.89d {+16d 53' 25"}
SUN_DIST:        113.06 [deg]   Sun_angle= 7.3 [hr] (West of Sun)
MOON_POSTN:       51.65d {+03h 26m 35s}  +13.58d {+13d 34' 33"}
MOON_DIST:        39.99 [deg]
MOON_ILLUM:      42 [%]
GAL_COORDS:      176.79,-74.65 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       16.93,-26.18 [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 = 176.55,-10.56 [deg].  
COMMENTS:           
COMMENTS:        NOTE: This BAT event is temporally(0.0<100sec) coincident with the FERMI_GBM event (trignum=555166961).

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sun 05 Aug 18 13:03:00 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      50
TRIGGER_NUM:     555166961
GRB_RA:           36.933d {+02h 27m 44s} (J2000),
                  37.188d {+02h 28m 45s} (current),
                  36.248d {+02h 25m 00s} (1950)
GRB_DEC:         +15.067d {+15d 04' 00"} (J2000),
                 +15.149d {+15d 08' 57"} (current),
                 +14.843d {+14d 50' 35"} (1950)
GRB_ERROR:       9.90 [deg radius, statistical plus systematic]
GRB_INTEN:       419 [cnts/sec]
DATA_SIGNIF:     11.60 [sigma]
INTEG_TIME:      0.256 [sec]
GRB_DATE:        18335 TJD;   217 DOY;   18/08/05
GRB_TIME:        46956.52 SOD {13:02:36.52} UT
GRB_PHI:         250.00 [deg]
GRB_THETA:        30.00 [deg]
DATA_TIME_SCALE: 0.2560 [sec]
HARD_RATIO:      0.34
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      92%  GRB
2nd_MOST_LIKELY:   4%  GRO_J0422_32
DETECTORS:       0,0,0, 0,0,0, 1,1,0, 0,0,0, 0,0,
SUN_POSTN:       135.54d {+09h 02m 09s}  +16.89d {+16d 53' 25"}
SUN_DIST:         93.34 [deg]   Sun_angle= 6.6 [hr] (West of Sun)
MOON_POSTN:       51.65d {+03h 26m 35s}  +13.58d {+13d 34' 34"}
MOON_DIST:        14.09 [deg]
MOON_ILLUM:      42 [%]
GAL_COORDS:      154.81,-41.77 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       39.48,  0.44 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2018/bn180805543/quicklook/glg_lc_medres34_bn180805543.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 276.45,1.40 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(0.0<100sec) coincident with the SWIFT_BAT event (trignum=851855).

GCN NOTICE

TITLE:          GCN/INTEGRAL NOTICE
NOTICE_DATE:    Sun 05 Aug 18 13:03:11 UT
NOTICE_TYPE:    INTEGRAL SPI ACS Trigger
TRIGGER_NUM:    8117,   Sub_Num: 0
GRB_INTEN:      9.53 [sigma]   
GRB_TIME:       46956.87 SOD {13:02:36.87} UT
GRB_DATE:       18335 TJD;   217 DOY;   18/08/05
COMMENTS:       INTEGRAL SPI_ACS GRB Trigger.
COMMENTS:       Time_Scale=0.2000 and Time_Error=0.1000.
COMMENTS:
COMMENTS:       NOTE: This SPIACS event is temporally(0.0<100sec) coincident with the FERMI_GBM event (trignum=555166961).
COMMENTS:
COMMENTS:       The SPIACS lightcurve can be found at:
COMMENTS:       ftp://isdcarc.unige.ch/arc/FTP/ibas/spiacs/2018-08/2018-08-05T13-02-36.6868-05986-43920-0.lc

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 05 Aug 18 13:04:19 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     851855,   Seg_Num: 0
GRB_RA:           25.7783d {+01h 43m 06.79s} (J2000),
                  26.0023d {+01h 44m 00.55s} (current),
                  25.1758d {+01h 40m 42.19s} (1950)
GRB_DEC:         -17.4915d {-17d 29' 29.3"} (J2000),
                 -17.3984d {-17d 23' 54.1"} (current),
                 -17.7428d {-17d 44' 34.1"} (1950)
GRB_ERROR:       5.5 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.14e-09 [erg/cm2/sec]
GRB_SIGNIF:      6.48 [sigma]
IMG_START_DATE:  18335 TJD;   217 DOY;   18/08/05
IMG_START_TIME:  47033.26 SOD {13:03:53.26} UT,   76.8 [sec] since BAT Trigger Time
TAM[0-3]:        327.67 237.20 261.67 243.70
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       135.54d {+09h 02m 09s}  +16.89d {+16d 53' 24"}
SUN_DIST:        113.09 [deg]   Sun_angle= 7.3 [hr] (West of Sun)
MOON_POSTN:       51.66d {+03h 26m 38s}  +13.58d {+13d 34' 47"}
MOON_DIST:        40.01 [deg]
MOON_ILLUM:      42 [%]
GAL_COORDS:      176.67,-74.67 [deg] galactic lon,lat of the burst
ECL_COORDS:       16.90,-26.15 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 2.13 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 05 Aug 18 13:06:37 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     851855,   Seg_Num: 0
GRB_RA:           25.813d {+01h 43m 15s} (J2000),
                  26.037d {+01h 44m 09s} (current),
                  25.211d {+01h 40m 51s} (1950)
GRB_DEC:         -17.503d {-17d 30' 11"} (J2000),
                 -17.410d {-17d 24' 36"} (current),
                 -17.755d {-17d 45' 15"} (1950)
GRB_DATE:        18335 TJD;   217 DOY;   18/08/05
GRB_TIME:        46956.47 SOD {13:02:36.47} UT
TRIGGER_INDEX:   481
GRB_PHI:         -42.05 [deg]
GRB_THETA:        28.71 [deg]
DELTA_TIME:      -24.00 [sec]
TRIGGER_DUR:     0.256 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     27.98 [sigma]
IMAGE_SIGNIF:    10.44 [sigma]
LC_URL:          sw00851855000msb.lc
SUN_POSTN:       135.54d {+09h 02m 10s}  +16.89d {+16d 53' 23"}
SUN_DIST:        113.06 [deg]   Sun_angle= 7.3 [hr] (West of Sun)
MOON_POSTN:       51.68d {+03h 26m 43s}  +13.59d {+13d 35' 08"}
MOON_DIST:        40.02 [deg]
MOON_ILLUM:      42 [%]
GAL_COORDS:      176.79,-74.65 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       16.93,-26.18 [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 = 176.55,-10.56 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 05 Aug 18 13:04:27 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     851855,   Seg_Num: 0
GRB_RA:           25.7783d {+01h 43m 06.7s} (J2000),
                  26.0023d {+01h 44m 00.5s} (current),
                  25.1758d {+01h 40m 42.1s} (1950)
GRB_DEC:         -17.4915d {-17d 29' 29.3"} (J2000),
                 -17.3984d {-17d 23' 54.1"} (current),
                 -17.7428d {-17d 44' 34.1"} (1950)
GRB_ERROR:       5.4 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       42 [cnts]
IMG_START_DATE:  18335 TJD;   217 DOY;   18/08/05
IMG_START_TIME:  47033.26 SOD {13:03:53.26} UT,   76.8 [sec] since BAT Trigger Time
CENTROID_X:      325.48,  raw= 325  [pixels]
CENTROID_Y:      325.33,  raw= 325  [pixels]
ROLL:            78.71 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   63.49
GRB_POS_XRT_Z:   44.98
IMAGE_URL:       sw00851855000msxps_rw.img
SUN_POSTN:       135.54d {+09h 02m 09s}  +16.89d {+16d 53' 24"}
SUN_DIST:        113.09 [deg]   Sun_angle= 7.3 [hr] (West of Sun)
MOON_POSTN:       51.66d {+03h 26m 38s}  +13.58d {+13d 34' 48"}
MOON_DIST:        40.01 [deg]
MOON_ILLUM:      42 [%]
GAL_COORDS:      176.67,-74.67 [deg] galactic lon,lat of the burst
ECL_COORDS:       16.90,-26.15 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 05 Aug 18 13:04:31 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     851855,   Seg_Num: 0
GRB_RA:           25.7783d {+01h 43m 06.7s} (J2000),
                  26.0023d {+01h 44m 00.5s} (current),
                  25.1758d {+01h 40m 42.1s} (1950)
GRB_DEC:         -17.4915d {-17d 29' 29.3"} (J2000),
                 -17.3984d {-17d 23' 54.1"} (current),
                 -17.7428d {-17d 44' 34.1"} (1950)
GRB_ERROR:       5.4 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       42 [cnts]
IMG_START_DATE:  18335 TJD;   217 DOY;   18/08/05
IMG_START_TIME:  47033.26 SOD {13:03:53.26} UT,   76.8 [sec] since BAT Trigger Time
CENTROID_X:      325.48,  raw= 325  [pixels]
CENTROID_Y:      325.33,  raw= 325  [pixels]
ROLL:            78.71 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   63.49
GRB_POS_XRT_Z:   44.98
IMAGE_URL:       sw00851855000msxps_rw.img
SUN_POSTN:       135.54d {+09h 02m 09s}  +16.89d {+16d 53' 24"}
SUN_DIST:        113.09 [deg]   Sun_angle= 7.3 [hr] (West of Sun)
MOON_POSTN:       51.66d {+03h 26m 38s}  +13.58d {+13d 34' 49"}
MOON_DIST:        40.01 [deg]
MOON_ILLUM:      42 [%]
GAL_COORDS:      176.67,-74.67 [deg] galactic lon,lat of the burst
ECL_COORDS:       16.90,-26.15 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 05 Aug 18 13:07:04 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     851855,   Seg_Num: 0
POINT_RA:         25.795d {+01h 43m 11s} (J2000)
POINT_DEC:       -17.507d {-17d 30' 23"} (J2000)
POINT_ROLL:      78.710d
IMG_START_DATE:  18335 TJD;   217 DOY;   18/08/05
IMG_START_TIME:  47041.33 SOD {13:04:01.33} UT,   84.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.004
N_STARS:         17
X_OFFSET:        600 [pixels]
Y_OFFSET:        488 [pixels]
X_MAX:           1559 [pixels]
Y_MAX:           1447 [pixels]
DET_THRESH:      12
PHOTO_THRESH:    6
SL_URL:          sw00851855000msufc0084.fits
SUN_POSTN:       135.54d {+09h 02m 10s}  +16.89d {+16d 53' 22"}
SUN_DIST:        113.08 [deg]   Sun_angle= 7.3 [hr] (West of Sun)
MOON_POSTN:       51.68d {+03h 26m 44s}  +13.59d {+13d 35' 13"}
MOON_DIST:        40.03 [deg]
MOON_ILLUM:      42 [%]
GAL_COORDS:      176.76,-74.66 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       16.91,-26.17 [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:     Sun 05 Aug 18 13:06:53 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     851855,   Seg_Num: 0
POINT_RA:         25.795d {+01h 43m 11s} (J2000)
POINT_DEC:       -17.507d {-17d 30' 23"} (J2000)
POINT_ROLL:      78.710d
IMG_START_DATE:  18335 TJD;   217 DOY;   18/08/05
IMG_START_TIME:  47041.33 SOD {13:04:01.33} UT,   84.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.004
N_STARS:         17
X_OFFSET:        600 [pixels]
Y_OFFSET:        488 [pixels]
X_MAX:           1559 [pixels]
Y_MAX:           1447 [pixels]
DET_THRESH:      12
PHOTO_THRESH:    6
SL_URL:          sw00851855000msufc0084.fits
SUN_POSTN:       135.54d {+09h 02m 10s}  +16.89d {+16d 53' 22"}
SUN_DIST:        113.08 [deg]   Sun_angle= 7.3 [hr] (West of Sun)
MOON_POSTN:       51.68d {+03h 26m 44s}  +13.59d {+13d 35' 11"}
MOON_DIST:        40.03 [deg]
MOON_ILLUM:      42 [%]
GAL_COORDS:      176.76,-74.66 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       16.91,-26.17 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 05 Aug 18 13:08:14 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     851855,   Seg_Num: 0
POINT_RA:         25.795d {+01h 43m 11s} (J2000)
POINT_DEC:       -17.507d {-17d 30' 23"} (J2000)
ROLL:            78.710d
IMG_START_DATE:  18335 TJD;   217 DOY;   18/08/05
IMG_START_TIME:  47041.33 SOD {13:04:01.33} UT,   84.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     555167062
X_OFFSET:        670 [pixels]
Y_OFFSET:        806 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       830
Y_GRB_POS:       966
BINNING_INDEX:   1
IM_URL:          sw00851855000msuni0106.fits
SUN_POSTN:       135.54d {+09h 02m 10s}  +16.89d {+16d 53' 22"}
SUN_DIST:        113.08 [deg]   Sun_angle= 7.3 [hr] (West of Sun)
MOON_POSTN:       51.69d {+03h 26m 47s}  +13.59d {+13d 35' 24"}
MOON_DIST:        40.04 [deg]
MOON_ILLUM:      42 [%]
GAL_COORDS:      176.76,-74.66 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       16.91,-26.17 [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:     Sun 05 Aug 18 13:08:21 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     851855,   Seg_Num: 0
POINT_RA:         25.795d {+01h 43m 11s} (J2000)
POINT_DEC:       -17.507d {-17d 30' 23"} (J2000)
ROLL:            78.710d
IMG_START_DATE:  18335 TJD;   217 DOY;   18/08/05
IMG_START_TIME:  47041.33 SOD {13:04:01.33} UT,   84.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     555167062
X_OFFSET:        670 [pixels]
Y_OFFSET:        806 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       830
Y_GRB_POS:       966
BINNING_INDEX:   1
IM_URL:          sw00851855000msuni0106.fits
SUN_POSTN:       135.54d {+09h 02m 10s}  +16.89d {+16d 53' 21"}
SUN_DIST:        113.08 [deg]   Sun_angle= 7.3 [hr] (West of Sun)
MOON_POSTN:       51.70d {+03h 26m 47s}  +13.59d {+13d 35' 25"}
MOON_DIST:        40.04 [deg]
MOON_ILLUM:      42 [%]
GAL_COORDS:      176.76,-74.66 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       16.91,-26.17 [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:     Sun 05 Aug 18 13:14:45 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     851855,   Seg_Num: 0
POINT_RA:         25.793d {+01h 43m 10s} (J2000)
POINT_DEC:       -17.506d {-17d 30' 21"} (J2000)
POINT_ROLL:      78.710d
IMG_START_DATE:  18335 TJD;   217 DOY;   18/08/05
IMG_START_TIME:  47253.15 SOD {13:07:33.15} UT,   296.7 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.521
N_STARS:         12
X_OFFSET:        350 [pixels]
Y_OFFSET:        486 [pixels]
X_MAX:           1309 [pixels]
Y_MAX:           1445 [pixels]
DET_THRESH:      7
PHOTO_THRESH:    3
SL_URL:          sw00851855000msufc0296.fits
SUN_POSTN:       135.55d {+09h 02m 11s}  +16.89d {+16d 53' 17"}
SUN_DIST:        113.09 [deg]   Sun_angle= 7.3 [hr] (West of Sun)
MOON_POSTN:       51.76d {+03h 27m 01s}  +13.61d {+13d 36' 25"}
MOON_DIST:        40.10 [deg]
MOON_ILLUM:      42 [%]
GAL_COORDS:      176.75,-74.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       16.91,-26.17 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 05 Aug 18 13:14:59 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     851855,   Seg_Num: 0
POINT_RA:         25.793d {+01h 43m 10s} (J2000)
POINT_DEC:       -17.506d {-17d 30' 21"} (J2000)
POINT_ROLL:      78.710d
IMG_START_DATE:  18335 TJD;   217 DOY;   18/08/05
IMG_START_TIME:  47253.15 SOD {13:07:33.15} UT,   296.7 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.521
N_STARS:         12
X_OFFSET:        350 [pixels]
Y_OFFSET:        486 [pixels]
X_MAX:           1309 [pixels]
Y_MAX:           1445 [pixels]
DET_THRESH:      7
PHOTO_THRESH:    3
SL_URL:          sw00851855000msufc0296.fits
SUN_POSTN:       135.55d {+09h 02m 11s}  +16.89d {+16d 53' 17"}
SUN_DIST:        113.09 [deg]   Sun_angle= 7.3 [hr] (West of Sun)
MOON_POSTN:       51.76d {+03h 27m 02s}  +13.61d {+13d 36' 27"}
MOON_DIST:        40.10 [deg]
MOON_ILLUM:      42 [%]
GAL_COORDS:      176.75,-74.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       16.91,-26.17 [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:     Sun 05 Aug 18 13:15:51 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     851855,   Seg_Num: 0
POINT_RA:         25.793d {+01h 43m 10s} (J2000)
POINT_DEC:       -17.506d {-17d 30' 21"} (J2000)
ROLL:            78.710d
IMG_START_DATE:  18335 TJD;   217 DOY;   18/08/05
IMG_START_TIME:  47253.15 SOD {13:07:33.15} UT,   296.7 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     555167274
X_OFFSET:        670 [pixels]
Y_OFFSET:        806 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       830
Y_GRB_POS:       966
BINNING_INDEX:   1
IM_URL:          sw00851855000msuni0318.fits
SUN_POSTN:       135.55d {+09h 02m 11s}  +16.89d {+16d 53' 16"}
SUN_DIST:        113.09 [deg]   Sun_angle= 7.3 [hr] (West of Sun)
MOON_POSTN:       51.77d {+03h 27m 04s}  +13.61d {+13d 36' 35"}
MOON_DIST:        40.10 [deg]
MOON_ILLUM:      42 [%]
GAL_COORDS:      176.75,-74.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       16.91,-26.17 [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:     Sun 05 Aug 18 13:16:05 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     851855,   Seg_Num: 0
POINT_RA:         25.793d {+01h 43m 10s} (J2000)
POINT_DEC:       -17.506d {-17d 30' 21"} (J2000)
ROLL:            78.710d
IMG_START_DATE:  18335 TJD;   217 DOY;   18/08/05
IMG_START_TIME:  47253.15 SOD {13:07:33.15} UT,   296.7 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     555167274
X_OFFSET:        670 [pixels]
Y_OFFSET:        806 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       830
Y_GRB_POS:       966
BINNING_INDEX:   1
IM_URL:          sw00851855000msuni0318.fits
SUN_POSTN:       135.55d {+09h 02m 11s}  +16.89d {+16d 53' 16"}
SUN_DIST:        113.09 [deg]   Sun_angle= 7.3 [hr] (West of Sun)
MOON_POSTN:       51.77d {+03h 27m 04s}  +13.61d {+13d 36' 38"}
MOON_DIST:        40.11 [deg]
MOON_ILLUM:      42 [%]
GAL_COORDS:      176.75,-74.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       16.91,-26.17 [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:     Sun 05 Aug 18 13:15:18 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     851855,   Seg_Num: 0
GRB_RA:           25.7816d {+01h 43m 07.58s} (J2000),
                  26.0056d {+01h 44m 01.35s} (current),
                  25.1791d {+01h 40m 42.98s} (1950)
GRB_DEC:         -17.4926d {-17d 29' 33.3"} (J2000),
                 -17.3995d {-17d 23' 58.1"} (current),
                 -17.7439d {-17d 44' 38.1"} (1950)
GRB_ERROR:       2.2 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  18335 TJD;   217 DOY;   18/08/05
IMG_START_TIME:  47238.00 SOD {13:07:18.00} UT,   281.5 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       135.55d {+09h 02m 11s}  +16.89d {+16d 53' 17"}
SUN_DIST:        113.10 [deg]   Sun_angle= 7.3 [hr] (West of Sun)
MOON_POSTN:       51.76d {+03h 27m 03s}  +13.61d {+13d 36' 30"}
MOON_DIST:        40.10 [deg]
MOON_ILLUM:      42 [%]
GAL_COORDS:      176.69,-74.66 [deg] galactic lon,lat of the burst
ECL_COORDS:       16.91,-26.15 [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 Circular #23076
P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), N. P. M. Kuin (UCL-MSSL), A. Y. Lien (GSFC/UMBC), F. E. Marshall (NASA/GSFC), A. Melandri (INAF-OAB) and B. Sbarufatti (PSU) report on behalf of the Neil Gehrels Swift Observatory Team:
At 13:02:36 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 180805B (trigger=851855). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 25.813, -17.503 which is
```
   RA(J2000) = 01h 43m 15s
   Dec(J2000) = -17d 30' 11"
```
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 1.5 sec. The peak count rate was ~4000 counts/sec (15-350 keV), at ~0.1 sec after the trigger.
The XRT began observing the field at 13:03:53.2 UT, 76.8 seconds after the BAT trigger. Using promptly downlinked data we find a bright, fading, uncatalogued X-ray source with an enhanced position: RA, Dec 25.7814, -17.4926 which is equivalent to:
```
   RA(J2000)  = 01h 43m 07.55s
   Dec(J2000) = -17d 29' 33.2"
```
with an uncertainty of 2.1 arcseconds (radius, 90% containment). This location is 114 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 (1.63 x 10^20 cm^-2, Willingale et al. 2013), with an excess column of 3.1 (+2.89/-2.44) x 10^21 cm^-2 (90% confidence).
The initial flux in the 2.5 s image was 1.14e-09 erg cm^-2 s^-1 (0.2-10 keV).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 84 seconds after the BAT trigger. No credible afterglow candidate has been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. The 8'x8' region for the list of sources generated on-board covers 100% of the XRT error circle. The list of sources is typically complete to about 18 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.02.
Burst Advocate for this burst is P. D'Avanzo (paolo.davanzo AT brera.inaf.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 NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 05 Aug 18 13:20:09 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     851855,   Seg_Num: 0
POINT_RA:         25.793d {+01h 43m 10s} (J2000)
POINT_DEC:       -17.506d {-17d 30' 20"} (J2000)
POINT_ROLL:      78.709d
IMG_START_DATE:  18335 TJD;   217 DOY;   18/08/05
IMG_START_TIME:  47829.46 SOD {13:17:09.46} UT,   873.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.861
N_STARS:         136
X_OFFSET:        110 [pixels]
Y_OFFSET:        246 [pixels]
X_MAX:           1549 [pixels]
Y_MAX:           1685 [pixels]
DET_THRESH:      11
PHOTO_THRESH:    6
SL_URL:          sw00851855000msufc0872.fits
SUN_POSTN:       135.55d {+09h 02m 12s}  +16.89d {+16d 53' 13"}
SUN_DIST:        113.09 [deg]   Sun_angle= 7.3 [hr] (West of Sun)
MOON_POSTN:       51.81d {+03h 27m 13s}  +13.62d {+13d 37' 16"}
MOON_DIST:        40.14 [deg]
MOON_ILLUM:      42 [%]
GAL_COORDS:      176.75,-74.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       16.91,-26.17 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 05 Aug 18 13:20:22 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     851855,   Seg_Num: 0
POINT_RA:         25.793d {+01h 43m 10s} (J2000)
POINT_DEC:       -17.506d {-17d 30' 20"} (J2000)
POINT_ROLL:      78.709d
IMG_START_DATE:  18335 TJD;   217 DOY;   18/08/05
IMG_START_TIME:  47829.46 SOD {13:17:09.46} UT,   873.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.861
N_STARS:         136
X_OFFSET:        110 [pixels]
Y_OFFSET:        246 [pixels]
X_MAX:           1549 [pixels]
Y_MAX:           1685 [pixels]
DET_THRESH:      11
PHOTO_THRESH:    6
SL_URL:          sw00851855000msufc0872.fits
SUN_POSTN:       135.55d {+09h 02m 12s}  +16.89d {+16d 53' 13"}
SUN_DIST:        113.09 [deg]   Sun_angle= 7.3 [hr] (West of Sun)
MOON_POSTN:       51.81d {+03h 27m 14s}  +13.62d {+13d 37' 18"}
MOON_DIST:        40.14 [deg]
MOON_ILLUM:      42 [%]
GAL_COORDS:      176.75,-74.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       16.91,-26.17 [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:     Sun 05 Aug 18 13:21:29 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     851855,   Seg_Num: 0
POINT_RA:         25.793d {+01h 43m 10s} (J2000)
POINT_DEC:       -17.506d {-17d 30' 20"} (J2000)
ROLL:            78.709d
IMG_START_DATE:  18335 TJD;   217 DOY;   18/08/05
IMG_START_TIME:  47829.46 SOD {13:17:09.46} UT,   873.0 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     555167850
X_OFFSET:        669 [pixels]
Y_OFFSET:        805 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       829
Y_GRB_POS:       965
BINNING_INDEX:   1
IM_URL:          sw00851855000msuni0894.fits
SUN_POSTN:       135.55d {+09h 02m 12s}  +16.89d {+16d 53' 13"}
SUN_DIST:        113.09 [deg]   Sun_angle= 7.3 [hr] (West of Sun)
MOON_POSTN:       51.82d {+03h 27m 16s}  +13.62d {+13d 37' 28"}
MOON_DIST:        40.15 [deg]
MOON_ILLUM:      42 [%]
GAL_COORDS:      176.75,-74.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       16.91,-26.17 [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:     Sun 05 Aug 18 13:21:41 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     851855,   Seg_Num: 0
POINT_RA:         25.793d {+01h 43m 10s} (J2000)
POINT_DEC:       -17.506d {-17d 30' 20"} (J2000)
ROLL:            78.709d
IMG_START_DATE:  18335 TJD;   217 DOY;   18/08/05
IMG_START_TIME:  47829.46 SOD {13:17:09.46} UT,   873.0 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     555167850
X_OFFSET:        669 [pixels]
Y_OFFSET:        805 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       829
Y_GRB_POS:       965
BINNING_INDEX:   1
IM_URL:          sw00851855000msuni0894.fits
SUN_POSTN:       135.55d {+09h 02m 12s}  +16.89d {+16d 53' 12"}
SUN_DIST:        113.09 [deg]   Sun_angle= 7.3 [hr] (West of Sun)
MOON_POSTN:       51.82d {+03h 27m 17s}  +13.63d {+13d 37' 30"}
MOON_DIST:        40.15 [deg]
MOON_ILLUM:      42 [%]
GAL_COORDS:      176.75,-74.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       16.91,-26.17 [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 #23077
P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team.
Using 1323 s of XRT Photon Counting mode data and 1 UVOT images for GRB 180805B, 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 = 25.78171, -17.49345 which is equivalent to:
```
RA (J2000): 01h 43m 7.61s
Dec (J2000): -17d 29' 36.4"
```
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 #23078
R. Hamburg (UAH), A. von Kienlin (MPE), and C. Meegan (UAH) report on behalf of the Fermi GBM Team:
"At 13:02:36.52 UT on 05 August 2018, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 180805B (trigger 555166961 / 180805543) which was also detected by the Swift BAT and XRT instruments (D'Avanzo et al. 2018, GCN 23076). The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight at the GBM trigger time is 64 degrees.
The GBM light curve shows a single peak with a duration (T90) of about 1 s (50-300 keV). The time-averaged spectrum from T0-0.13 s to T0+0.58 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.5 +/- 0.2 and the cutoff energy, parameterized as Epeak, is 346 +/- 75 keV.
The event fluence (10-1000 keV) in this time interval is (5.9 +/- 0.7)E-07 erg/cm^2. The 64-ms peak photon flux measured starting from T0+0.06 s in the 10-1000 keV band is 8.3 +/- 1.1 ph/s/cm^2.
The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN Circular #23080
N. P. M. Kuin (UCL-MSSL) and P. D'Avanzo (INAF-OAB) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 180805B 85 s after the BAT trigger (D'Avanzo et al., GCN Circ. 23076). No optical afterglow consistent with the XRT position (Evans et al. GCN Circ. 23077) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent exposures are:
```
Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC            85          235          147         >20.8
u_FC               297          546          246         >20.2
white               85         1544          392         >21.3
v                  626         1421           78         >18.6
b                  552         1519           97         >20.0
u                  297          546          246         >20.2
w1                 675         1470           97         >18.8
m2                1078         1097           19         >17.8
w2                 774         1569           78         >19.0
```
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 #23082
T. Sakamoto (AGU), S. D. Barthelmy (GSFC), J. R. Cummings (CPI), P. D'Avanzo (INAF-OAB), H. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), J. P. Norris (BSU), D. M. Palmer (LANL), 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 180805B (trigger #851855) (D'Avanzo et al., GCN Circ. 23076). The BAT ground-calculated position is RA, Dec = 25.877, -17.475 deg which is
```
  RA(J2000)  =  01h 43m 30.6s
  Dec(J2000) = -17d 28' 29.3"
```
with an uncertainty of 3.1 arcmin, (radius, sys+stat, 90% containment). The partial coding was 67%.
The mask-weighted light curve show a short pulse that starts from ~T-0.1 s, peaks at ~T+0.1 s, and ends at ~T+0.7 s. The short pulse is followed by some weak emission that lasts until ~ T+130 s. T90 (15-350 keV) is 122.5 +- 18.3 sec (estimated error including systematics).
The time-averaged spectrum from T-0.10 to T+127.46 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.13 +- 0.29. The fluence in the 15-150 keV band is 9.6 +- 1.7 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T-0.11 sec in the 15-150 keV band is 1.7 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
The structure of the burst shows similarity to those of short GRBs with extended emission. We thus perform further analysis on the short spike and the tail emission.
The spectrum of the short pulse from T-0.001 to T+0.712 sec can be fitted by a simple power-law model with power-law index of 0.66 +- 0.20 and fluence (15-150 keV) of 1.7 +- 0.2 x 10^-7 erg/cm2. The spectrum of the extended emission from T+0.712 to T+126.532 sec is best fit by a simple power-law model, with power-law index of 1.16 +- 0.39 and fluence (15-150 keV) of 6.8 +- 1.6 x 10^-7 erg/cm2. These values are consistent with those of short GRBs with extended emission (Lien & Sakamoto et al. 2016).
The lag analysis does not produce a well-constrained value due to the weakness of the short pulse.
The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/851855/BA/
GCN Circular #23083
S. J. LaPorte (PSU), J.A. Kennea (PSU), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), A. Melandri (INAF-OAB), V. D'Elia (ASDC), B. Sbarufatti (INAF-OAB/PSU) and P. D'Avanzo report on behalf of the Swift-XRT team:
We have analysed 6.6 ks of XRT data for GRB 180805B (D'Avanzo et al. GCN Circ. 23076), from 82 s to 36.7 ks after the BAT trigger. The data comprise 197 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Evans et al. (GCN Circ. 23077).
The light curve can be modelled with a series of power-law decays. The light curve initially rises, with an index alpha=-1.5 (+0.0, -0.5). At T+102 s it breaks to an alpha of 1.61 (+0.15, -0.65). The light curve breaks again at T+241 s to a decay with alpha=3.1 (+/-0.4), before a final break at T+891 s s after which the decay index is 0.88 (+0.21, -0.18).
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 0.93 (+0.09, -0.06). The best-fitting absorption column is 2.3 (+4.7, -0.7) x 10^20 cm^-2, consistent with the Galactic value of 1.6 x 10^20 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 1.90 (+0.25, -0.23) and a best-fitting absorption column of 7.3 (+6.6, -5.4) x 10^20 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.5 x 10^-11 (4.0 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     7.3 (+6.6, -5.4) x 10^20 cm^-2
Galactic foreground: 1.6 x 10^20 cm^-2
Excess significance: 1.7 sigma
Photon index:	     1.90 (+0.25, -0.23)
```
If the light curve continues to decay with a power-law decay index of 0.88, the count rate at T+24 hours will be 2.0 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 6.8 x 10^-14 (7.8 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/00851855.
This circular is an official product of the Swift-XRT team.
GCN Circular #23085
V. Lipunov, N.Tiurina, E. Gorbovskoy, V.Kornilov, A.Kuznetsov, V.Chazov, I. Gorbunov, D.Zimnukhov, D.Kuvshinov, P.Balanutsa, V.Vladimirov, D. Vlasenko Lomonosov Moscow State University,SAI
D. Buckley, South African Astronomical Observatory (SAAO)
R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias (IAC)
A. Tlatov, V.Senik, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory
R. Podesta, F. Podesta, C. Lopez, C.Francile Observatorio Astronomico Felix Aguilar (OAFA)
H.Levato, Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)
O. Gres, N.M.Budnev , Yu.Ishmuhametova Irkutsk State University (ISU)
A. Gabovich, V. Yurkov, Yu. Sergienko Blagoveschensk Educational State University (BSPU)
MASTER-SAAO robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in SAAO was starting survey on the Swift short GRB with extended emission GRB180805B (D'Avanzo et al., GCN #23076; Hamburg et al., GCN #23078;Sakamoto et al., GCN #23082) error-box (Evans et al., GCN #23077; ) 37838 sec after notice time and 38322 sec after trigger time at 2018-08-05 23:46:00 UT. The 5-sigma upper limit on our first (180s exposure) set is about 20.5 mag
There is no OT detected.
The message may be cited.
GCN Circular #23086
D. B. Malesani (DAWN/NBI and DARK/NBI), G. Pugliese (API/Univ. Amsterdam), P. D'Avanzo (INAF/Brera), N. R. Tanvir (Univ. Leicester), K. Wiersema (Univ. Warwick), report on behalf of the Stargate consortium:
We observed the field of GRB 180805B, classified as short with extended emission (D'Avanzo et al., GCN 23076; Sakamoto et al., GCN 23082), using the ESO Telescopes located in Cerro Paranal. Optical and near-infrared observations were obtained using the FORS2 and HAWK-I instruments, respectively. No counterpart is detected inside the UVOT-enhanced XRT error circle (Evans et al., GCN 23077) in either images, with the 3-sigma upper limits summarized in the table below.
```
Filter  Mid time (UT)  Time since GRB (hr)  Limiting mag (Vega)
---------------------------------------------------------------
J       Aug 6.245      16.84                23.5
R       Aug 6.363      19.67                25.5
```
Calibration was carried out against a single 2MASS star for the J band, and using archival FORS2 zeropoints for the R band.
We note the presence of four extended objects within a few arcsec of the center of the XRT error circle, including a source 3.5" North of the GRB (R ~ 22.5) also visible in the Pan-STARRS r and i images. Their association with the GRB cannot be assessed at the present time.
We acknowledge excellent support from the ESO observing staff in Paranal, especially Stephane Brillant, Joe Anderson, and Bian Fuyan. DBM also acknowledges useful discussion with Amy Lien (GSFC/UMBC) about the classification of this GRB.
GCN Circular #23087
G.Ramsay (Armagh O.), K.Ulaczyk, D.Steeghs, J.Lyman (U. Warwick), M.Dyer (U. Sheffield), B.Gompertz, A.Levan, R.Cutter (U. Warwick) K. Ackley, D.Galloway, E.Rol (Monash U.), V.Dhillon (U. Sheffield), P.O'Brien, R.Starling (U. Leicester), S.Poshyachinda (NARIT), D.Pollacco (U. Warwick), E.Thrane (Monash U.), E.Palle (IAC)
report on behalf of the GOTO collaboration:
In response to GRB 180805B (D'Avanzo et al. GCN 23076), the Gravitational-wave Optical Transient Observer (GOTO) observed the field near the Swift BAT/XRT detection.
Observations started at 2018-08-06T04:37:59 UT (15.5 hours after the burst) consisting of a set of 6x120s exposures in our wide L filter (400-700nm). We do not detect any optical source within the error circle of the enhanced XRT location (Evans et al. GCN 23077) with a 5-sigma limit of V=20.4, using APASS calibrators on the stacked image.
We note that our observations were obtained between those of Lupinov et al. GCN 23085 and Malesani et al. GCN 23086.
GOTO is operated at the La Palma observing facilities of the University of Warwick on behalf of a consortium including the University of Warwick, Monash University, Armagh Observatory, the University of Leicester, the University of Sheffield, the National Astronomical Research Institute of Thailand (NARIT) and the Instituto de Astrofisica de Canarias (IAC)
https://goto-observatory.org/
GCN Circular #23088
Y.-D. Hu, F.J. Aceituno, J. C. Tello and A.J. Castro-Tirado (IAA-CSIC Granada), on behalf of a larger collaboration, report:
Following the detection of GRB 180805B (short burst with extended emission) by Swift (D'Avanzo et al. GCNC 23076, Sakamoto et al. GCNC 23082), optical images in the I-band were obtained at the 1.5m OSN telescope in Granada (Spain) starting at 03:08 (Aug 6), i.e. ~14 h postburst. No optical afterglow is detected in the co-added image (7 x 300s, mid time at 03:26 UT, 14.4 h after the trigger) within the enhanced Swift/XRT error box (Evans et al. GCNC 23077) down to I=21.0, which is in agreement with the non-detections reported by Lipunov et al. (GCNC 23085), Malesani et al. (GCNC 23086) and Ramsay et al.(GCNC 23087).
GCN Circular #23089
Alan M. Watson (UNAM), Nat Butler (ASU), Rosa L. Becerra (UNAM), William H. Lee (UNAM), Carlos Rom�n-Z��iga (UNAM), Alexander Kutyrev (GSFC), and Eleonora Troja (GSFC) report:
We observed the field of the short GRB 180805B (D'Avanzo et al., GCN Circ. 23076) with the COATLI 50-cm telescope and interim imager at the Observatorio Astron�mico Nacional on the Sierra de San Pedro M�rtir (http://coatli.astroscu.unam.mx) from 2018-08-06 08:01 to 11:48 UTC (18.98 to 22.77 hours after the trigger), obtaining a total of 2.98 hours of exposure in the w filter.
We do not detect any optical sources within the enhanced XRT error region (Evans et al., GCN Circ. 23077) to a 5-sigma limiting magnitude of
w > 22.5
This magnitude is calibrated against the USNO-B1 catalog (adjusted to an approximate AB system) and is not corrected for Galactic extinction in the direction of the GRB.
We thank the COATLI technical team (Fernando �ngeles, Oscar Chapa, Salvador Cuevas, Alejandro Farah, Jorge Fuentes, Rosal�a Langarica, Fernando Quir�s, and Carlos Tejada) and the staff of the Observatorio Astron�mico Nacional.
GCN Circular #23090
A. Higgins (Univ. Leicester), K. Wiersema (Univ. Warwick) and D. B. Malesani (DAWN/NBI and DARK/NBI) report:
We observed the field of GRB 180805B, classified as short with extended emission (D'Avanzo et al., GCN 23076; Sakamoto et al., GCN 23082), using the ESO New Technology Telescope (NTT) equipped with the EFOSC2 camera. Our observations consist of 9 images in i band, for a total of 1800 s exposure, with mid time 2018 August 6.28 UT (17.76 hr after the GRB trigger), and were obtained as part of the SPLOT programme (Higgins et al. 2018, subm.).
No counterpart is detected inside the UVOT-enhanced XRT error circle (Evans et al., GCN 23077) in our coadded image, down to a 3-sigma upper limit i > 25 (AB), adopting i = 20.56 for the Pan-STARRS star at RA = 01:43:07.462, Dec = -17:28:30.90.
We thank D. Castex for support with these observations.
GCN Circular #23108
Daniele B. Malesani (DAWN/NBI and DARK/NBI) and Nicolas Crouzet (IAC) report:
We observed the field of the short GRB 180805B (D'Avanzo et al., GCN 23076; Sakamoto et al., GCN 23082) using one of the 40-cm telescopes located in the Teide observatory (Canary Islands), part of the Las Cumbres Observatory network.
Observations consisted of 9x300 s exposures in the SDSS r filter, centered around the mean epoch Aug 6.19 UT (15.49 hr after the GRB). The PSF delivered to the image is around 3".
No object is detected within or close to the X-ray afterglow error circle (Evans et al., GCN 23077), down to a 3-sigma limiting magnitude of r = 20 AB, calibrated using nearby stars from the Pan-STARRS catalog.
Redshift z= 0.6609 +- 0.0004 from host galaxy emission (Hbeta, Hgamma, [OIII], [OII])
B. O'Connor et al. 2022, MN 515, 4890
Redshift z= 0.6612 +- 0.002 from host galaxy emission (Halpha, Hbeta, [OII], [OIII])
W.-F. Fong et al. 2022, ApJ 940, 56

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