Gamma-ray Burst 181010A

(All information courtesy of the instrument teams.)

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Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 10 Oct 18 05:56:12 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     866434,   Seg_Num: 0
GRB_RA:           52.557d {+03h 30m 14s} (J2000),
                  52.763d {+03h 31m 03s} (current),
                  52.011d {+03h 28m 03s} (1950)
GRB_DEC:         -23.035d {-23d 02' 06"} (J2000),
                 -22.972d {-22d 58' 18"} (current),
                 -23.206d {-23d 12' 19"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       2617 [cnts]    Image_Peak=154 [image_cnts]
TRIGGER_DUR:     1.024 [sec] 
TRIGGER_INDEX:   146     E_range: 25-100 keV
BKG_INTEN:       15693 [cnts]
BKG_TIME:        21338.27 SOD {05:55:38.27} UT
BKG_DUR:         8 [sec]
GRB_DATE:        18401 TJD;   283 DOY;   18/10/10
GRB_TIME:        21351.71 SOD {05:55:51.71} UT
GRB_PHI:         -152.81 [deg]
GRB_THETA:        26.51 [deg]
SOLN_STATUS:     0x20000003
RATE_SIGNIF:     12.64 [sigma]
IMAGE_SIGNIF:    7.39 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +2  -3  +0  +0 +68  +0 
SUN_POSTN:       195.56d {+13h 02m 15s}   -6.63d {-06d 38' 01"}
SUN_DIST:        133.11 [deg]   Sun_angle= 9.5 [hr] (West of Sun)
MOON_POSTN:      210.58d {+14h 02m 18s}   -7.12d {-07d 06' 54"}
MOON_DIST:       142.90 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      215.40,-53.96 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       42.61,-40.51 [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 = 337.68,19.21 [deg].  
COMMENTS:           
COMMENTS:        NOTE: This BAT event is temporally(8.0<100sec) coincident with the FERMI_GBM event (trignum=560843764).

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Wed 10 Oct 18 05:56:24 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      49
TRIGGER_NUM:     560843764
GRB_RA:           54.867d {+03h 39m 28s} (J2000),
                  55.072d {+03h 40m 17s} (current),
                  54.320d {+03h 37m 17s} (1950)
GRB_DEC:         -22.333d {-22d 19' 59"} (J2000),
                 -22.273d {-22d 16' 23"} (current),
                 -22.495d {-22d 29' 40"} (1950)
GRB_ERROR:       13.08 [deg radius, statistical plus systematic]
GRB_INTEN:       166 [cnts/sec]
DATA_SIGNIF:     7.60 [sigma]
INTEG_TIME:      1.024 [sec]
GRB_DATE:        18401 TJD;   283 DOY;   18/10/10
GRB_TIME:        21359.39 SOD {05:55:59.39} UT
GRB_PHI:         118.00 [deg]
GRB_THETA:        50.00 [deg]
DATA_TIME_SCALE: 1.0240 [sec]
HARD_RATIO:      0.57
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      95%  GRB
2nd_MOST_LIKELY:   4%  Generic Transient
DETECTORS:       0,0,0, 0,0,0, 0,0,0, 1,1,0, 0,0,
SUN_POSTN:       195.56d {+13h 02m 15s}   -6.63d {-06d 38' 01"}
SUN_DIST:        131.71 [deg]   Sun_angle= 9.4 [hr] (West of Sun)
MOON_POSTN:      210.58d {+14h 02m 19s}   -7.12d {-07d 06' 56"}
MOON_DIST:       142.06 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      215.22,-51.72 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       45.56,-40.51 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2018/bn181010247/quicklook/glg_lc_medres34_bn181010247.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 223.62,-2.18 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(8.0<100sec) coincident with the SWIFT_BAT event (trignum=866434).

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Wed 10 Oct 18 05:56:41 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      60
TRIGGER_NUM:     560843764
GRB_RA:           61.370d {+04h 05m 29s} (J2000),
                  61.587d {+04h 06m 21s} (current),
                  60.792d {+04h 03m 10s} (1950)
GRB_DEC:         -14.310d {-14d 18' 35"} (J2000),
                 -14.260d {-14d 15' 35"} (current),
                 -14.445d {-14d 26' 40"} (1950)
GRB_ERROR:       7.83 [deg radius, statistical only]
DATA_SIGNIF:     8.30 [sigma]
DATA_INTERVAL:   1.024 [sec]
GRB_DATE:        18401 TJD;   283 DOY;   18/10/10
GRB_TIME:        21359.39 SOD {05:55:59.39} UT
GRB_PHI:         120.00 [deg]
GRB_THETA:        60.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4153 (Gnd S/W Version number)
SUN_POSTN:       195.56d {+13h 02m 15s}   -6.63d {-06d 38' 01"}
SUN_DIST:        129.79 [deg]   Sun_angle= 8.9 [hr] (West of Sun)
MOON_POSTN:      210.58d {+14h 02m 20s}   -7.12d {-07d 07' 00"}
MOON_DIST:       142.54 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      207.21,-43.16 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       55.75,-34.41 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2018/bn181010247/quicklook/glg_lc_medres34_bn181010247.gif
POS_MAP_URL:     http://gcn.gsfc.nasa.gov/notices_f/gbm_gnd_loc_map_560843764.fits
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        In the LAT Field-of-view.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        The LC_URL file will not be created/available until ~15 min after the trigger.  
COMMENTS:        The POS_MAP_URL file will not be created/available until ~1.5 min after the notice.  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(8.0<100sec) coincident with the SWIFT_BAT event (trignum=866434).

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Wed 10 Oct 18 06:05:03 UT
NOTICE_TYPE:     Fermi-GBM Final Position
RECORD_NUM:      0
TRIGGER_NUM:     560843764
GRB_RA:           60.640d {+04h 02m 34s} (J2000),
                  60.856d {+04h 03m 25s} (current),
                  60.065d {+04h 00m 16s} (1950)
GRB_DEC:         -15.020d {-15d 01' 11"} (J2000),
                 -14.969d {-14d 58' 07"} (current),
                 -15.158d {-15d 09' 27"} (1950)
GRB_ERROR:       7.16 [deg radius, statistical only]
GRB_DATE:        18401 TJD;   283 DOY;   18/10/10
GRB_TIME:        21359.39 SOD {05:55:59.39} UT
GRB_PHI:         120.00 [deg]
GRB_THETA:        59.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   41531 (Gnd S/W Version number)
SUN_POSTN:       195.57d {+13h 02m 17s}   -6.64d {-06d 38' 09"}
SUN_DIST:        130.19 [deg]   Sun_angle= 9.0 [hr] (West of Sun)
MOON_POSTN:      210.66d {+14h 02m 38s}   -7.14d {-07d 08' 38"}
MOON_DIST:       142.78 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      207.72,-44.09 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       54.72,-34.93 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2018/bn181010247/quicklook/glg_lc_medres34_bn181010247.gif
LOC_URL:         http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2018/bn181010247/quicklook/glg_locplot_all_bn181010247.png
COMMENTS:        Fermi-GBM Final Position.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        The LC_URL file should be available by the time this FINAL notice is produced.  
COMMENTS:        This notice was generated completely by automated pipeline processing.  
COMMENTS:        This is likely a Short GRB.  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(8.0<100sec) coincident with the SWIFT_BAT event (trignum=866434).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 10 Oct 18 05:57:33 UT
NOTICE_TYPE:     Swift-XRT Nack-Position
TRIGGER_NUM:     866434,   Seg_Num: 0
POINT_RA:         52.561d {+03h 30m 15s} (J2000)
POINT_DEC:       -23.041d {-23d 02' 27"} (J2000)
IMG_START_DATE:  18401 TJD;   283 DOY;   18/10/10
IMG_START_TIME:  21444.75 SOD {05:57:24.75} UT,   93.0 [sec] since BAT Trigger Time
COUNTS:          14    Min_needed= 20
STD_DEV:         0.00   Max_StdDev_for_Good=28.44 [arcsec]
PH2_ITER:        2    Max_iter_allowed= 4
ERROR_CODE:      1
COMMENTS:        SWIFT-XRT Nack Position.  
COMMENTS:        No source found in the image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 10 Oct 18 05:59:51 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     866434,   Seg_Num: 0
GRB_RA:           52.557d {+03h 30m 14s} (J2000),
                  52.763d {+03h 31m 03s} (current),
                  52.011d {+03h 28m 03s} (1950)
GRB_DEC:         -23.035d {-23d 02' 06"} (J2000),
                 -22.972d {-22d 58' 18"} (current),
                 -23.206d {-23d 12' 19"} (1950)
GRB_DATE:        18401 TJD;   283 DOY;   18/10/10
GRB_TIME:        21351.71 SOD {05:55:51.71} UT
TRIGGER_INDEX:   146
GRB_PHI:         -152.81 [deg]
GRB_THETA:        26.51 [deg]
DELTA_TIME:      -63.00 [sec]
TRIGGER_DUR:     1.024 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     12.64 [sigma]
IMAGE_SIGNIF:    7.39 [sigma]
LC_URL:          sw00866434000msb.lc
SUN_POSTN:       195.57d {+13h 02m 16s}   -6.63d {-06d 38' 04"}
SUN_DIST:        133.11 [deg]   Sun_angle= 9.5 [hr] (West of Sun)
MOON_POSTN:      210.61d {+14h 02m 26s}   -7.13d {-07d 07' 37"}
MOON_DIST:       142.91 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      215.40,-53.96 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       42.61,-40.51 [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 = 337.68,19.21 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 10 Oct 18 06:00:37 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     866434,   Seg_Num: 0
POINT_RA:         52.561d {+03h 30m 15s} (J2000)
POINT_DEC:       -23.041d {-23d 02' 26"} (J2000)
POINT_ROLL:      124.866d
IMG_START_DATE:  18401 TJD;   283 DOY;   18/10/10
IMG_START_TIME:  21447.87 SOD {05:57:27.87} UT,   96.2 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.687
N_STARS:         21
X_OFFSET:        438 [pixels]
Y_OFFSET:        543 [pixels]
X_MAX:           1397 [pixels]
Y_MAX:           1502 [pixels]
DET_THRESH:      11
PHOTO_THRESH:    5
SL_URL:          sw00866434000msufc0096.fits
SUN_POSTN:       195.57d {+13h 02m 16s}   -6.63d {-06d 38' 05"}
SUN_DIST:        133.10 [deg]   Sun_angle= 9.5 [hr] (West of Sun)
MOON_POSTN:      210.62d {+14h 02m 28s}   -7.13d {-07d 07' 46"}
MOON_DIST:       142.91 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      215.42,-53.96 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       42.62,-40.52 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 10 Oct 18 06:00:48 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     866434,   Seg_Num: 0
POINT_RA:         52.561d {+03h 30m 15s} (J2000)
POINT_DEC:       -23.041d {-23d 02' 26"} (J2000)
POINT_ROLL:      124.866d
IMG_START_DATE:  18401 TJD;   283 DOY;   18/10/10
IMG_START_TIME:  21447.87 SOD {05:57:27.87} UT,   96.2 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.687
N_STARS:         21
X_OFFSET:        438 [pixels]
Y_OFFSET:        543 [pixels]
X_MAX:           1397 [pixels]
Y_MAX:           1502 [pixels]
DET_THRESH:      11
PHOTO_THRESH:    5
SL_URL:          sw00866434000msufc0096.fits
SUN_POSTN:       195.57d {+13h 02m 16s}   -6.64d {-06d 38' 05"}
SUN_DIST:        133.10 [deg]   Sun_angle= 9.5 [hr] (West of Sun)
MOON_POSTN:      210.62d {+14h 02m 28s}   -7.13d {-07d 07' 48"}
MOON_DIST:       142.91 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      215.42,-53.96 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       42.62,-40.52 [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:     Wed 10 Oct 18 06:01:55 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     866434,   Seg_Num: 0
POINT_RA:         52.561d {+03h 30m 15s} (J2000)
POINT_DEC:       -23.041d {-23d 02' 26"} (J2000)
ROLL:            124.866d
IMG_START_DATE:  18401 TJD;   283 DOY;   18/10/10
IMG_START_TIME:  21447.87 SOD {05:57:27.87} UT,   96.2 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     560843869
X_OFFSET:        757 [pixels]
Y_OFFSET:        862 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       917
Y_GRB_POS:       1022
BINNING_INDEX:   1
IM_URL:          sw00866434000msuni0118.fits
SUN_POSTN:       195.57d {+13h 02m 16s}   -6.64d {-06d 38' 06"}
SUN_DIST:        133.10 [deg]   Sun_angle= 9.5 [hr] (West of Sun)
MOON_POSTN:      210.63d {+14h 02m 31s}   -7.13d {-07d 08' 01"}
MOON_DIST:       142.91 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      215.42,-53.96 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       42.62,-40.52 [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:     Wed 10 Oct 18 06:02:05 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     866434,   Seg_Num: 0
POINT_RA:         52.561d {+03h 30m 15s} (J2000)
POINT_DEC:       -23.041d {-23d 02' 26"} (J2000)
ROLL:            124.866d
IMG_START_DATE:  18401 TJD;   283 DOY;   18/10/10
IMG_START_TIME:  21447.87 SOD {05:57:27.87} UT,   96.2 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     560843869
X_OFFSET:        757 [pixels]
Y_OFFSET:        862 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       917
Y_GRB_POS:       1022
BINNING_INDEX:   1
IM_URL:          sw00866434000msuni0118.fits
SUN_POSTN:       195.57d {+13h 02m 16s}   -6.64d {-06d 38' 06"}
SUN_DIST:        133.10 [deg]   Sun_angle= 9.5 [hr] (West of Sun)
MOON_POSTN:      210.63d {+14h 02m 31s}   -7.13d {-07d 08' 03"}
MOON_DIST:       142.91 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      215.42,-53.96 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       42.62,-40.52 [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 NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 10 Oct 18 06:02:06 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     866434,   Seg_Num: 0
GRB_RA:           52.5695d {+03h 30m 16.67s} (J2000),
                  52.7747d {+03h 31m 05.93s} (current),
                  52.0230d {+03h 28m 05.52s} (1950)
GRB_DEC:         -23.0373d {-23d 02' 14.2"} (J2000),
                 -22.9739d {-22d 58' 26.1"} (current),
                 -23.2076d {-23d 12' 27.2"} (1950)
GRB_ERROR:       4.1 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  18401 TJD;   283 DOY;   18/10/10
IMG_START_TIME:  21544.00 SOD {05:59:04.00} UT,   192.3 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       195.57d {+13h 02m 16s}   -6.64d {-06d 38' 06"}
SUN_DIST:        133.10 [deg]   Sun_angle= 9.5 [hr] (West of Sun)
MOON_POSTN:      210.63d {+14h 02m 31s}   -7.13d {-07d 08' 03"}
MOON_DIST:       142.91 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      215.41,-53.95 [deg] galactic lon,lat of the burst
ECL_COORDS:       42.63,-40.52 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
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:        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:     Wed 10 Oct 18 06:04:45 UT
NOTICE_TYPE:     Swift-UVOT Position
TRIGGER_NUM:     866434,   Seg_Num: 0
GRB_RA:           52.5703d {+03h 30m 16.87s} (J2000),
                  52.7755d {+03h 31m 06.13s} (current),
                  52.0238d {+03h 28m 05.72s} (1950)
GRB_DEC:         -23.0376d {-23d 02' 15.3"} (J2000),
                 -22.9742d {-22d 58' 27.2"} (current),
                 -23.2079d {-23d 12' 28.3"} (1950)
GRB_ERROR:       0.8 [arcsec radius, statistical only]
GRB_MAG:         19.37 +/- 0.16 [mag]
FILTER:          10, White
IMG_START_DATE:  18401 TJD;   283 DOY;   18/10/10
IMG_START_TIME:  21444.00 SOD {05:57:24.00} UT,   92.3 [sec] since BAT Trigger Time
SUN_POSTN:       195.57d {+13h 02m 17s}   -6.64d {-06d 38' 09"}
SUN_DIST:        133.10 [deg]   Sun_angle= 9.5 [hr] (West of Sun)
MOON_POSTN:      210.65d {+14h 02m 37s}   -7.14d {-07d 08' 34"}
MOON_DIST:       142.92 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      215.41,-53.95 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       42.63,-40.52 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT UVOT Position Notice.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        Result based on Genie data.  
COMMENTS:        Notice generated automatically.

GCN Circular #23309
A. Melandri (INAF-OAB), S. D. Barthelmy (GSFC), M. J. Moss (George Washington University), K. L. Page (U Leicester) and B. Sbarufatti (PSU) report on behalf of the Neil Gehrels Swift Observatory Team:
At 05:55:51 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 181010A (trigger=866434). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 52.557, -23.035, which is
```
   RA(J2000)  =  03h 30m 14s
   Dec(J2000) = -23d 02' 06"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows multiple peaks with a total duration of about 25 sec. The peak count rate was ~2200 counts/sec (15-350 keV), at ~8 sec after the trigger.
The XRT began observing the field at 05:57:24.7 UT, 93.0 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source located at RA, Dec 52.56984, -23.03721 which is equivalent to:
```
   RA(J2000)  = 03h 30m 16.76s
   Dec(J2000) = -23d 02' 14.0"
```
with an uncertainty of 3.6 arcseconds (radius, 90% containment). This location is 43 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 (1.89 x 10^20 cm^-2, Willingale et al. 2013), with an excess column of 5.9 (+2.46/-2.18) x 10^21 cm^-2 (90% confidence).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 96 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at
```
  RA(J2000)  =	03:30:16.89 =  52.57036
  DEC(J2000) = -23:02:15.4  = -23.03760
```
with a 90%-confidence error radius of about 0.78 arc sec. This position is 3.0 arc sec. from the center of the XRT error circle. The estimated magnitude is 19.37 with a 1-sigma error of about 0.16. No correction has been made for the expected extinction corresponding to E(B-V) of 0.03.
Burst Advocate for this burst is A. Melandri (andrea.melandri 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:     Wed 10 Oct 18 06:09:04 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     866434,   Seg_Num: 0
POINT_RA:         52.558d {+03h 30m 14s} (J2000)
POINT_DEC:       -23.041d {-23d 02' 25"} (J2000)
POINT_ROLL:      124.870d
IMG_START_DATE:  18401 TJD;   283 DOY;   18/10/10
IMG_START_TIME:  21660.39 SOD {06:01:00.39} UT,   308.7 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.789
N_STARS:         21
X_OFFSET:        198 [pixels]
Y_OFFSET:        303 [pixels]
X_MAX:           1637 [pixels]
Y_MAX:           1742 [pixels]
DET_THRESH:      8
PHOTO_THRESH:    3
SL_URL:          sw00866434000msufc0308.fits
SUN_POSTN:       195.57d {+13h 02m 17s}   -6.64d {-06d 38' 13"}
SUN_DIST:        133.11 [deg]   Sun_angle= 9.5 [hr] (West of Sun)
MOON_POSTN:      210.69d {+14h 02m 46s}   -7.16d {-07d 09' 25"}
MOON_DIST:       142.93 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      215.41,-53.96 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       42.61,-40.52 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 10 Oct 18 06:09:18 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     866434,   Seg_Num: 0
POINT_RA:         52.558d {+03h 30m 14s} (J2000)
POINT_DEC:       -23.041d {-23d 02' 25"} (J2000)
POINT_ROLL:      124.870d
IMG_START_DATE:  18401 TJD;   283 DOY;   18/10/10
IMG_START_TIME:  21660.39 SOD {06:01:00.39} UT,   308.7 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.789
N_STARS:         21
X_OFFSET:        198 [pixels]
Y_OFFSET:        303 [pixels]
X_MAX:           1637 [pixels]
Y_MAX:           1742 [pixels]
DET_THRESH:      8
PHOTO_THRESH:    3
SL_URL:          sw00866434000msufc0308.fits
SUN_POSTN:       195.57d {+13h 02m 17s}   -6.64d {-06d 38' 13"}
SUN_DIST:        133.11 [deg]   Sun_angle= 9.5 [hr] (West of Sun)
MOON_POSTN:      210.70d {+14h 02m 47s}   -7.16d {-07d 09' 28"}
MOON_DIST:       142.93 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      215.41,-53.96 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       42.61,-40.52 [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:     Wed 10 Oct 18 06:10:15 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     866434,   Seg_Num: 0
POINT_RA:         52.558d {+03h 30m 14s} (J2000)
POINT_DEC:       -23.041d {-23d 02' 25"} (J2000)
ROLL:            124.870d
IMG_START_DATE:  18401 TJD;   283 DOY;   18/10/10
IMG_START_TIME:  21660.39 SOD {06:01:00.39} UT,   308.7 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     560844082
X_OFFSET:        757 [pixels]
Y_OFFSET:        862 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       917
Y_GRB_POS:       1022
BINNING_INDEX:   1
IM_URL:          sw00866434000msuni0330.fits
SUN_POSTN:       195.57d {+13h 02m 18s}   -6.64d {-06d 38' 14"}
SUN_DIST:        133.11 [deg]   Sun_angle= 9.5 [hr] (West of Sun)
MOON_POSTN:      210.70d {+14h 02m 49s}   -7.16d {-07d 09' 39"}
MOON_DIST:       142.93 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      215.41,-53.96 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       42.61,-40.52 [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:     Wed 10 Oct 18 06:10:22 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     866434,   Seg_Num: 0
POINT_RA:         52.558d {+03h 30m 14s} (J2000)
POINT_DEC:       -23.041d {-23d 02' 25"} (J2000)
ROLL:            124.870d
IMG_START_DATE:  18401 TJD;   283 DOY;   18/10/10
IMG_START_TIME:  21660.39 SOD {06:01:00.39} UT,   308.7 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     560844082
X_OFFSET:        757 [pixels]
Y_OFFSET:        862 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       917
Y_GRB_POS:       1022
BINNING_INDEX:   1
IM_URL:          sw00866434000msuni0330.fits
SUN_POSTN:       195.57d {+13h 02m 18s}   -6.64d {-06d 38' 14"}
SUN_DIST:        133.11 [deg]   Sun_angle= 9.5 [hr] (West of Sun)
MOON_POSTN:      210.71d {+14h 02m 49s}   -7.16d {-07d 09' 40"}
MOON_DIST:       142.93 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      215.41,-53.96 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       42.61,-40.52 [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 NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 10 Oct 18 06:09:36 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     866434,   Seg_Num: 0
GRB_RA:           52.5705d {+03h 30m 16.92s} (J2000),
                  52.7757d {+03h 31m 06.17s} (current),
                  52.0240d {+03h 28m 05.76s} (1950)
GRB_DEC:         -23.0382d {-23d 02' 17.5"} (J2000),
                 -22.9748d {-22d 58' 29.3"} (current),
                 -23.2085d {-23d 12' 30.4"} (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:  18401 TJD;   283 DOY;   18/10/10
IMG_START_TIME:  21544.00 SOD {05:59:04.00} UT,   192.3 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       195.57d {+13h 02m 17s}   -6.64d {-06d 38' 13"}
SUN_DIST:        133.10 [deg]   Sun_angle= 9.5 [hr] (West of Sun)
MOON_POSTN:      210.70d {+14h 02m 48s}   -7.16d {-07d 09' 31"}
MOON_DIST:       142.93 [deg]
MOON_ILLUM:      2 [%]
GAL_COORDS:      215.41,-53.95 [deg] galactic lon,lat of the burst
ECL_COORDS:       42.63,-40.52 [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 #23310
E. Gorbovskoy, V. Lipunov, V.Kornilov, D.Kuvshinov, N.Tyurina, P.Balanutsa,A.Kuznetsov, V.V.Chazov, D. Vlasenko Lomonosov Moscow State University, Sternberg Astronomical Institute
R. Podesta, F. Podesta, C. Lopez, C.Francile Observatorio Astronomico Felix Aguilar (OAFA)
Hugo Levato Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)
R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias
D. Buckley, South African Astronomical Observatory
A. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory
O. Gres, N.M. Budnev, Yu.Ishmuhametova Applied Physics Institute of Irkutsk State University
V. Yurkov, A. Gabovich, Yu. Sergienko Blagoveschensk Educational State University, Blagoveschensk
MASTER-OAFA robotic telescope (MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) was pointed to the GRB181010.25 19 sec after notice time and 42 sec after trigger time at 2018-10-10 05:56:33 UT. On our first (60s coadd exposure) coadd set we found 1 optical transient within SWIFT error-box (ra=52.55 dec=-23.0344 r=0.05) brighter than 18.24.
```
  T-Tmid      Date      Time       Expt.        Ra                Dec 
Mag
---------|---------------------|-------|-----------------|-----------------|-------
       72   2018-10-10 05:56:33      60   (  3h 30m 16.8s , -23d  2m 14.9s) 
18.05
```
The 5-sigma upper limit has been about 18.7 mag The message may be cited.
====================================================================
The galactic latitude b = -53 deg., longitude l = 215 deg. The observations made on zenit distance = 15 deg.The moon ( 2 % bright part) below the horizon (The altitude of the Moon is -50 deg. ). The sun altitude is -45.7 deg. The object can be observed till sunrise at 2018-10-10 10:03:45 .
THIS BLOCK FOR MASTER-Team USERS ONLY.
Link to GRB181010.25 page: https://200.123.254.238:49004//master2/grb.php?not=2018-10-10+05%3A56%3A14&sat=SWIFT&gcrd=%2852.55d%2C-23.0344d%29&eb=0.05&trig=2018-10-10+05%3A55%3A51&n=GRB181010.25
Long transients in E.B. https://200.123.254.238:49004//master2/trans.php?wh=transients.coord2000@%27%3C%2852.55d%2C-23.0344d%29%2C0.1d%3E%27%3A%3Ascircle+and+transients.datetime%3E%3D%272018-10-10+05%3A55%3A51%27&class=9&t2=SWIFT+GRB181010.25+optical+counterpart+candidate
Short transients in E.B. https://200.123.254.238:49004//master2/trans3.php?wh=transients3.coord2000@%27%3C%2852.55d%2C-23.0344d%29%2C0.1d%3E%27%3A%3Ascircle+and+transients3.datetime%3E%3D%272018-10-10+05%3A55%3A51%27&class=-1&t2=SWIFT+GRB181010.25+optical+counterpart+candidate
Two tube transients in E.B. https://200.123.254.238:49004//master2/trans2.php?wh=transients2.coord2000@%27%3C%2852.55d%2C-23.0344d%29%2C0.1d%3E%27%3A%3Ascircle+and+transients2.datetime%3E%3D%272018-10-10+05%3A55%3A51%27&class=0&t2=SWIFT+GRB181010.25+optical+counterpart+candidate
Undef. objects 1 image https://200.123.254.238:49004//master2/aobj.php?wh=stars.coord2000@%27%3C%2852.55d%2C-23.0344d%29%2C0.1d%3E%27%3A%3Ascircle+and+stars.class=0+and+stars.status+and+stars.proc_id=626837&t2=SWIFT+GRB181010.25+1+image+optical+counterpart+candidate
The observation and reduction will continue. This circular was generated automatically. The message may be cited.
GCN Circular #23311
R. Martone, C. Guidorzi (U. Ferrara), S. Kobayashi (LJMU), C.G. Mundell (U. Bath), A. Gomboc (U. Nova Gorica), I.A. Steele (LJMU), A. Cucchiara, D. Morris (U. of Virgin Islands) on behalf of a large collaboration report:
We automatically began observing Swift GRB 181010A (Melandri et al. GCN 23309) with one LCO 1-m unit at Cerro Tololo from October 10, 06:02:54 UT (corresponding to 7.1 minutes from the GRB trigger time) with the SDSS r' filter. We clearly detect the optical counterpart reported by Swift-UVOT with r'=19.98 +- 0.12 mag from a 3x120s exposure at a mid time of 10.7 minutes post GRB, as calibrated against nearby Pan-STARRS objects.
GCN Circular #23312
Eleonora Troja (GSFC), Alan M. Watson (UNAM), Nat Butler (ASU), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), Jesus Gonzalez (UNAM), Carlos Rom�n-Zuniga (UNAM), Harvey Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (U. Wash.), and Vicki Toy (UMD) report:
We observed the field of GRB 181010A (Melandri, et al., GCN 23309) with the Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the 1.5m Harold Johnson Telescope at the Observatorio Astronomico Nacional on Sierra San Pedro Martir from 2018/10 10.25 to 2018/10 10.29 UTC (4.2 min to 1.10 hours after the BAT trigger), obtaining a total of 0.50 hours exposure in the r and i bands and 0.24 hours exposure in the Z, Y, J, and H bands.
At the position of the optical afterglow (Melandri, et al., GCN 23309; Gorbovskoy, et al., GCN 23310), in comparison with the USNO-B1 and 2MASS catalogs, we obtain the following detections:
```
r��� 20.30 +/- 0.20
i��� 21.03 +/- 0.10
Z��� 20.67 +/- 0.24
Y��� 20.24 +/- 0.21
J��� 19.87 +/- 0.24
H�� 19.16 +/- 0.17
```
These magnitudes are in the AB system and are not corrected for Galactic extinction in the direction of the GRB.
We thank the staff of the Observatorio Astronomico Nacional in San Pedro Martir.
Further observations are on-going.
GCN Circular #23313
P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team.
Using 441 s of XRT Photon Counting mode data and 1 UVOT images for GRB 181010A, 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 = 52.57030, -23.03844 which is equivalent to:
```
RA (J2000): 03h 30m 16.87s
Dec (J2000): -23d 02' 18.4"
```
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 #23315
J-B. Vielfaure (CNRS - GEPI/Observatorie de Paris), J. Japelj (API, U. Amsterdam), D. B. Malesani (DAWN/NBI and DARK/NBI), V. D'Elia (SSDC), J. P. U. Fynbo (DAWN/NBI), N. R. Tanvir (Univ. Leicester), S. D. Vergani (CNRS - GEPI/Observatorie de Paris), A. Rossi (INAF-OAS), P. Vreeswijk (Radboud Univ. Nijmegen), L. Izzo (HETH/IAA-CSIC), D. A. Kann (HETH/IAA-CSIC), B. Milvang-Jensen (DAWN/NBI), D. Xu (NAOC) and K. E. Heintz (Univ. of Iceland), report on behalf of the Stargate collaboration:
We observed the optical counterpart of GRB 181010A (Melandri et al. GCN 23309; E. Gorbovskoy et al. 23310; R. Martone et al. 23311; E. Troja et al. 23312) with the ESO-VLT UT2 equipped with the X-shooter spectrograph. From the acquisition image we measure a preliminary magnitude of 20.4 +/- 0.1 mag in the r-band, calibrated against local Pan-STARRS sources. Several spectra with increasing exposure time were collected; in this analysis we consider only one with 600s exposure obtained in a Rapid Response Mode at 06:18:24.9 UT (at the start of observation, 0.37 hr after the GRB).
A bright continuum is observed across the entire wavelength range covered by X-shooter. Several absorption and emission features are detected, which can be identified as due to H-alpha and [OIII]5007/4959 in emission at z = 1.39. At this same redshift we also detect AlII1854/1862, SiII1808, the MgII doublet, and MgI in absorption. Fine-structure lines from FeII and NiII are also detected at z = 1.39, which makes the redshift association with the GRB secure. An intervening system at z = 0.67 with absorption features due to the MgII doublet and MgI is also identified in the spectrum.
We acknowledge the ESO observing staff at Paranal, in particular Jorge Lillo-Box.
GCN Circular #23316
P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), S. J. LaPorte (PSU), J.A. Kennea (PSU), B. Sbarufatti (INAF-OAB/PSU) and A. Melandri report on behalf of the Swift-XRT team:
We have analysed 7.3 ks of XRT data for GRB 181010A (Melandri et al. GCN Circ. 23309), from 96 s to 17.1 ks after the BAT trigger. The data comprise 77 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. 23313).
The light curve can be modelled with an initial power-law decay with an index of alpha=0.741 (+/-0.021), followed by a break at T+11.9 ks to an alpha of 3.6 (+4.4, -0.7).
A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 1.88 (+0.11, -0.10). The best-fitting absorption column is 3.1 (+/-0.5) x 10^21 cm^-2, in excess of the Galactic value of 1.9 x 10^20 cm^-2 (Willingale et al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 4.0 x 10^-11 (5.6 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     3.1 (+/-0.5) x 10^21 cm^-2
Galactic foreground: 1.9 x 10^20 cm^-2
Excess significance: 10.7 sigma
Photon index:	     1.88 (+0.11, -0.10)
```
If the light curve continues to decay with a power-law decay index of 3.6, the count rate at T+24 hours will be 1.8 x 10^-4 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 7.4 x 10^-15 (1.0 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/00866434.
This circular is an official product of the Swift-XRT team.
GCN Circular #23317
S.W.K. Emery (UCL-MSSL) and A. Melandri (INAF-OAB) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 181010A 96 s after the BAT trigger (Melandri et al., GCN Circ. 23309). A source consistent with the XRT position (Evans et al. GCN Circ. 23313) is detected in the initial UVOT exposures.
The preliminary UVOT position is:
```
    RA  (J2000) =  03:30:16.89 =  52.57038 (deg.)
    Dec (J2000) = -23:02:15.4  = -23.03761 (deg.)
```
with an estimated uncertainty of 0.49 arc sec. (radius, 90% confidence),
consistent with (MASTER-OAFA, Gorbovskoy et al., GCN Circ. 23310; LCO Cerro Tololo, Martone et al., GCN Circ. 23311; RATIR, Troja et al., GCN Circ. 23312; VLT/X-shooter, Vielfaure et al., GCN Circ. 23315)
Preliminary detections and 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            96          246          147        19.42 +/- 0.09
white              589         6359          247        >21.0
v                 3867         5503          393        >19.4
b                  564         6323          413        >20.9
u                  309         6117          639        >20.6
uvw1              4277         5912          393        >20.1
uvm2              4072         5707          393        >20.7
uvw2              5098         5298          197        >20.5
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.03 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #23319
T. Reynolds (Turku), S. Moran (Turku/NOT), P. D'Avanzo (INAF-OAB), D. B. Malesani (DAWN/NBI and DARK/NBI), M. De Pasquale (Istanbul Univ.), S. Campana, A. Melandri (INAF-OAB), J. Harmanen, H. Kuncarayakti (Turku), R. Cartier (CTIO), M. Dennefeld (IAP), C. Inserra (Southampton), E. Kankare (QUB), K. Maguire (QUB), S. J. Smartt (QUB), O. Yaron (Weizmann), D. R. Young (QUB), I. Manulis (Weizmann) report:
We observed the optical counterpart of GRB 181010A (Melandri et al. GCN 23309; Gorbovskoy et al. GCN 23310; Martone et al. GCN 23311; Troja et al. GCN 23312; Vielfaure et al. GCN 23315; Emery et al. GCN 23317) under the extended Public ESO Spectroscopic Survey for Transient Objects (ePESSTO; see Smartt et al. 2015, A&A, 579, 40; http://www.pessto.org ). The observations were performed on the ESO New Technology Telescope at La Silla with the EFOSC2 instrument in imaging mode starting from 2018-10-10 at 08:37:50 UT (i.e. 2.7 hours from the burst). The observations ended at 08:53:03 UT and were carried out with the R and i filters. The optical afterglow is clearly detected in the R-band image. From preliminary photometry, we find a magnitude of R ~ 22.9 +/- 0.1 (Vega, calibrated against the USNOB1 catalogue). The afterglow is marginally detected in the i-band. From preliminary forced photometry at the afterglow position, we derive a magnitude of i ~ 21.4 +/- 0.4 (AB, calibrated against the Pan-STARRS catalogue). These results, compared to previous reports (e.g. Martone et al. GCN 23311; Troja et al. GCN 23312; Vielfaure et al. GCN 23315), suggest for a significant fading of the optical afterglow flux.
GCN Circular #23320
A. von Kienlin (MPE) reports on behalf of the Fermi GBM Team:
"At 05:55:59.39 UT on 10 October 2018, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 181010A (trigger 560843764 / 181010247), which was also detected by the Swift/BAT (Melandri et al. 2018, GCN 23309). The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight at the GBM trigger time is 48.1 degrees.
The GBM light curve shows two structured pulses followed a weak tail with an overall duration (T90) of about 60 s (50-300 keV). The time-averaged spectrum from T0-0.256s to T0+1.280s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.8 +/- 0.2 and the cutoff energy, parameterized as Epeak, is 280 +/- 80 keV.
The event fluence (10-1000 keV) in this time interval is (6.13 +/- 0.98)E-07 erg/cm^2. The 1.024 sec peak photon flux measured starting from T0-0.128 s in the 10-1000 keV band is 3.35 +/- 0.29 ph/s/cm^2.
The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN Circular #23321
A. Y. Lien (GSFC/UMBC), S. D. Barthelmy (GSFC), J. R. Cummings (CPI), H. A. Krimm (NSF/USRA), C. B. Markwardt (GSFC), A. Melandri (INAF-OAB), 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-239 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 181010A (trigger #866434) (Melandri, et al., GCN Circ. 23309). The BAT ground-calculated position is RA, Dec = 52.574, -23.023 deg, which is
```
   RA(J2000)  =  03h 30m 17.7s 
   Dec(J2000) = -23d 01' 22.7" 
```
with an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment). The partial coding was 85%.
The mask-weighted light curve shows several overlapping peaks starting at ~T-5sec, peaking at ~T+8 sec, and returning to baseline at ~T+15 sec. T90 (15-350 keV) is 16.4 +- 2.2 sec (estimated error including systematics).
The time-averaged spectrum from T-4.04 to T+15.21 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.52 +- 0.15. The fluence in the 15-150 keV band is 6.9 +- 0.7 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+7.43 sec in the 15-150 keV band is 1.4 +- 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/866434/BA/
GCN Circular #23323
P. D'Avanzo, S.Covino, D. Fugazza, A. Melandri (INAF-OAB), on behalf of the REM team, report:
We observed the optical counterpart of GRB 181010A (Melandri et al. GCN 23309; Gorbovskoy et al. GCN 23310; Martone et al. GCN 23311; Troja et al. GCN 23312; Vielfaure et al. GCN 23315; Emery et al. GCN 23317; D'Avanzo et al. GCN 23319) with the REM 60cm robotic telescope located at the ESO premise of La Silla (Chile). The observations were performed starting on 2018 October 10 at 05:56:52 UT (i.e. 61 seconds after the burst) and were carried simultaneously in the g, r, i, z, and H bands.
The GRB afterglow is detected in the first set of optical and NIR images. From preliminary photometry we estimate the following magnitudes:
```
r = 18.2 +/- 0.2 (AB; calibrated against the Pan-STARRS catalogue)
H = 14.4 +/- 0.2 (Vega; calibrated against the 2MASS catalogue) 
```
at a mean time of 4.1 minutes from the GRB time (Melandri et al. GCN 23309).
GCN Circular #23326
P. Schady (Uni. of Bath, UK) and J. Bolmer (MPE, Garching) report:
We observed the field of GRB 181010A (Swift trigger 866434; Melandri et al., GCN #23309) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2 m MPG telescope at ESO La Silla Observatory (Chile).
Observations were performed in rapid response mode, and started at 05:59 UT, 3 mins after the GRB trigger. They were performed at an average seeing of 1.4" and at an average airmass of 1.0.
We detect a new source at a position consistent with the X-ray and optical afterglow (Gorbovskoy et al., GCN #23310; Evans et al., GCN #23313; Emery, GCN #23317). Based on the first 3.3 min of total exposures in g'r'i'z' and 3 min in JHK, we measure the following preliminary AB magnitudes:
```
g' = 20.02 +/- 0.02 mag
r' = 19.33 +/- 0.01 mag
i' = 19.13 +/- 0.02 mag
z' = 18.56 +/- 0.01 mag
J = 17.78 +/- 0.03 mag
H = 17.02 +/- 0.03 mag
```
Given magnitudes are calibrated against PanSTARRS and 2MASS field stars and are not corrected for the expected Galactic foreground extinction corresponding to a reddening of E_(B-V)=0.03 in the direction of the burst (Schlafly & Finkbeiner 2011).
We thank Markus Rabus for the excellend support from La Silla.

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Jochen Greiner, last update: 11-Oct-2018 [Disclaimer]