Gamma-ray Burst 180812A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 12 Aug 18 08:23:03 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     852903,   Seg_Num: 0
GRB_RA:          245.886d {+16h 23m 33s} (J2000),
                 245.780d {+16h 23m 07s} (current),
                 246.177d {+16h 24m 42s} (1950)
GRB_DEC:         +74.670d {+74d 40' 11"} (J2000),
                 +74.627d {+74d 37' 38"} (current),
                 +74.783d {+74d 46' 58"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       6160 [cnts]    Image_Peak=173 [image_cnts]
TRIGGER_DUR:     2.048 [sec] 
TRIGGER_INDEX:   263     E_range: 25-100 keV
BKG_INTEN:       62765 [cnts]
BKG_TIME:        30114.58 SOD {08:21:54.58} UT
BKG_DUR:         24 [sec]
GRB_DATE:        18342 TJD;   224 DOY;   18/08/12
GRB_TIME:        30150.23 SOD {08:22:30.23} UT
GRB_PHI:         139.05 [deg]
GRB_THETA:        38.36 [deg]
SOLN_STATUS:     0x20000003
RATE_SIGNIF:     11.22 [sigma]
IMAGE_SIGNIF:    7.57 [sigma]
MERIT_PARAMS:     +1  +0  +0  +1  +2  -2  +0  +0 -18  +0 
SUN_POSTN:       142.01d {+09h 28m 03s}  +14.94d {+14d 56' 22"}
SUN_DIST:         79.19 [deg]   Sun_angle= -6.9 [hr] (East of Sun)
MOON_POSTN:      155.49d {+10h 21m 57s}  +12.71d {+12d 42' 53"}
MOON_DIST:        77.82 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      107.89, 35.54 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      123.66, 78.76 [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 = 50.07,19.16 [deg].  
COMMENTS:           
COMMENTS:        NOTE: This BAT event is temporally(0.0<100sec) coincident with the FERMI_GBM event (trignum=555754955).

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sun 12 Aug 18 08:22:54 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      50
TRIGGER_NUM:     555754955
GRB_RA:          201.100d {+13h 24m 24s} (J2000),
                 201.229d {+13h 24m 55s} (current),
                 200.753d {+13h 23m 01s} (1950)
GRB_DEC:         +71.133d {+71d 07' 60"} (J2000),
                 +71.037d {+71d 02' 12"} (current),
                 +71.393d {+71d 23' 36"} (1950)
GRB_ERROR:       13.38 [deg radius, statistical plus systematic]
GRB_INTEN:       319 [cnts/sec]
DATA_SIGNIF:     8.00 [sigma]
INTEG_TIME:      0.256 [sec]
GRB_DATE:        18342 TJD;   224 DOY;   18/08/12
GRB_TIME:        30150.31 SOD {08:22:30.31} UT
GRB_PHI:          50.00 [deg]
GRB_THETA:        55.00 [deg]
DATA_TIME_SCALE: 0.2560 [sec]
HARD_RATIO:      0.15
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      96%  GRB
2nd_MOST_LIKELY:   2%  Cyg X-1
DETECTORS:       0,1,1, 0,0,0, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:       142.01d {+09h 28m 03s}  +14.94d {+14d 56' 22"}
SUN_DIST:         66.14 [deg]   Sun_angle= -3.9 [hr] (East of Sun)
MOON_POSTN:      155.49d {+10h 21m 57s}  +12.72d {+12d 42' 55"}
MOON_DIST:        64.57 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      119.12, 45.75 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      138.21, 66.13 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2018/bn180812349/quicklook/glg_lc_medres34_bn180812349.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 312.23,10.00 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 12 Aug 18 08:24:25 UT
NOTICE_TYPE:     Swift-XRT Nack-Position
TRIGGER_NUM:     852903,   Seg_Num: 0
POINT_RA:        245.869d {+16h 23m 29s} (J2000)
POINT_DEC:       +74.662d {+74d 39' 42"} (J2000)
IMG_START_DATE:  18342 TJD;   224 DOY;   18/08/12
IMG_START_TIME:  30257.66 SOD {08:24:17.66} UT,   107.4 [sec] since BAT Trigger Time
COUNTS:          1    Min_needed= 20
STD_DEV:         0.00   Max_StdDev_for_Good=28.44 [arcsec]
PH2_ITER:        0    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:     Sun 12 Aug 18 08:26:10 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     852903,   Seg_Num: 0
GRB_RA:          245.886d {+16h 23m 33s} (J2000),
                 245.780d {+16h 23m 07s} (current),
                 246.177d {+16h 24m 42s} (1950)
GRB_DEC:         +74.670d {+74d 40' 11"} (J2000),
                 +74.627d {+74d 37' 38"} (current),
                 +74.783d {+74d 46' 58"} (1950)
GRB_DATE:        18342 TJD;   224 DOY;   18/08/12
GRB_TIME:        30150.23 SOD {08:22:30.23} UT
TRIGGER_INDEX:   263
GRB_PHI:         139.05 [deg]
GRB_THETA:        38.36 [deg]
DELTA_TIME:      -43.00 [sec]
TRIGGER_DUR:     2.048 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     11.22 [sigma]
IMAGE_SIGNIF:    7.57 [sigma]
LC_URL:          sw00852903000msb.lc
SUN_POSTN:       142.01d {+09h 28m 04s}  +14.94d {+14d 56' 19"}
SUN_DIST:         79.19 [deg]   Sun_angle= -6.9 [hr] (East of Sun)
MOON_POSTN:      155.52d {+10h 22m 05s}  +12.71d {+12d 42' 19"}
MOON_DIST:        77.82 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      107.89, 35.54 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      123.66, 78.76 [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 = 50.07,19.16 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 12 Aug 18 08:28:52 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     852903,   Seg_Num: 0
POINT_RA:        245.868d {+16h 23m 28s} (J2000)
POINT_DEC:       +74.662d {+74d 39' 43"} (J2000)
POINT_ROLL:      287.247d
IMG_START_DATE:  18342 TJD;   224 DOY;   18/08/12
IMG_START_TIME:  30262.64 SOD {08:24:22.64} UT,   112.4 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        6.489
N_STARS:         20
X_OFFSET:        480 [pixels]
Y_OFFSET:        617 [pixels]
X_MAX:           1439 [pixels]
Y_MAX:           1576 [pixels]
DET_THRESH:      22
PHOTO_THRESH:    13
SL_URL:          sw00852903000msufc0112.fits
SUN_POSTN:       142.02d {+09h 28m 04s}  +14.94d {+14d 56' 17"}
SUN_DIST:         79.18 [deg]   Sun_angle= -6.9 [hr] (East of Sun)
MOON_POSTN:      155.55d {+10h 22m 12s}  +12.70d {+12d 41' 50"}
MOON_DIST:        77.82 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      107.88, 35.55 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      123.70, 78.76 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 12 Aug 18 08:28:17 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     852903,   Seg_Num: 0
GRB_RA:          245.8369d {+16h 23m 20.85s} (J2000),
                 245.7313d {+16h 22m 55.50s} (current),
                 246.1273d {+16h 24m 30.54s} (1950)
GRB_DEC:         +74.6643d {+74d 39' 51.4"} (J2000),
                 +74.6218d {+74d 37' 18.4"} (current),
                 +74.7776d {+74d 46' 39.4"} (1950)
GRB_ERROR:       4.0 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  18342 TJD;   224 DOY;   18/08/12
IMG_START_TIME:  30265.00 SOD {08:24:25.00} UT,   114.8 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       142.02d {+09h 28m 04s}  +14.94d {+14d 56' 18"}
SUN_DIST:         79.18 [deg]   Sun_angle= -6.9 [hr] (East of Sun)
MOON_POSTN:      155.54d {+10h 22m 10s}  +12.70d {+12d 41' 57"}
MOON_DIST:        77.81 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      107.89, 35.55 [deg] galactic lon,lat of the burst
ECL_COORDS:      123.72, 78.75 [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 0.58% < P(seren) < 1.1%.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 12 Aug 18 08:29:06 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     852903,   Seg_Num: 0
POINT_RA:        245.868d {+16h 23m 28s} (J2000)
POINT_DEC:       +74.662d {+74d 39' 43"} (J2000)
POINT_ROLL:      287.247d
IMG_START_DATE:  18342 TJD;   224 DOY;   18/08/12
IMG_START_TIME:  30262.64 SOD {08:24:22.64} UT,   112.4 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        6.489
N_STARS:         20
X_OFFSET:        480 [pixels]
Y_OFFSET:        617 [pixels]
X_MAX:           1439 [pixels]
Y_MAX:           1576 [pixels]
DET_THRESH:      22
PHOTO_THRESH:    13
SL_URL:          sw00852903000msufc0112.fits
SUN_POSTN:       142.02d {+09h 28m 04s}  +14.94d {+14d 56' 17"}
SUN_DIST:         79.18 [deg]   Sun_angle= -6.9 [hr] (East of Sun)
MOON_POSTN:      155.55d {+10h 22m 12s}  +12.70d {+12d 41' 48"}
MOON_DIST:        77.82 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      107.88, 35.55 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      123.70, 78.76 [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 12 Aug 18 08:30:28 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     852903,   Seg_Num: 0
POINT_RA:        245.868d {+16h 23m 28s} (J2000)
POINT_DEC:       +74.662d {+74d 39' 43"} (J2000)
ROLL:            287.247d
IMG_START_DATE:  18342 TJD;   224 DOY;   18/08/12
IMG_START_TIME:  30262.64 SOD {08:24:22.64} UT,   112.4 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     555755084
X_OFFSET:        799 [pixels]
Y_OFFSET:        936 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       959
Y_GRB_POS:       1096
BINNING_INDEX:   1
IM_URL:          sw00852903000msuni0134.fits
SUN_POSTN:       142.02d {+09h 28m 04s}  +14.94d {+14d 56' 16"}
SUN_DIST:         79.18 [deg]   Sun_angle= -6.9 [hr] (East of Sun)
MOON_POSTN:      155.57d {+10h 22m 16s}  +12.69d {+12d 41' 33"}
MOON_DIST:        77.82 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      107.88, 35.55 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      123.70, 78.76 [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 12 Aug 18 08:30:37 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     852903,   Seg_Num: 0
POINT_RA:        245.868d {+16h 23m 28s} (J2000)
POINT_DEC:       +74.662d {+74d 39' 43"} (J2000)
ROLL:            287.247d
IMG_START_DATE:  18342 TJD;   224 DOY;   18/08/12
IMG_START_TIME:  30262.64 SOD {08:24:22.64} UT,   112.4 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     555755084
X_OFFSET:        799 [pixels]
Y_OFFSET:        936 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       959
Y_GRB_POS:       1096
BINNING_INDEX:   1
IM_URL:          sw00852903000msuni0134.fits
SUN_POSTN:       142.02d {+09h 28m 04s}  +14.94d {+14d 56' 16"}
SUN_DIST:         79.18 [deg]   Sun_angle= -6.9 [hr] (East of Sun)
MOON_POSTN:      155.57d {+10h 22m 16s}  +12.69d {+12d 41' 31"}
MOON_DIST:        77.82 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      107.88, 35.55 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      123.70, 78.76 [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:     Sun 12 Aug 18 08:34:59 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     852903,   Seg_Num: 0
POINT_RA:        245.863d {+16h 23m 27s} (J2000)
POINT_DEC:       +74.663d {+74d 39' 48"} (J2000)
POINT_ROLL:      287.241d
IMG_START_DATE:  18342 TJD;   224 DOY;   18/08/12
IMG_START_TIME:  30420.73 SOD {08:27:00.73} UT,   270.5 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        2.515
N_STARS:         29
X_OFFSET:        240 [pixels]
Y_OFFSET:        377 [pixels]
X_MAX:           1679 [pixels]
Y_MAX:           1816 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw00852903000msufc0270.fits
SUN_POSTN:       142.02d {+09h 28m 05s}  +14.94d {+14d 56' 13"}
SUN_DIST:         79.18 [deg]   Sun_angle= -6.9 [hr] (East of Sun)
MOON_POSTN:      155.61d {+10h 22m 27s}  +12.68d {+12d 40' 44"}
MOON_DIST:        77.82 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      107.88, 35.55 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      123.70, 78.76 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 12 Aug 18 08:35:28 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     852903,   Seg_Num: 0
POINT_RA:        245.863d {+16h 23m 27s} (J2000)
POINT_DEC:       +74.663d {+74d 39' 48"} (J2000)
POINT_ROLL:      287.241d
IMG_START_DATE:  18342 TJD;   224 DOY;   18/08/12
IMG_START_TIME:  30420.73 SOD {08:27:00.73} UT,   270.5 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        2.515
N_STARS:         29
X_OFFSET:        240 [pixels]
Y_OFFSET:        377 [pixels]
X_MAX:           1679 [pixels]
Y_MAX:           1816 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw00852903000msufc0270.fits
SUN_POSTN:       142.02d {+09h 28m 05s}  +14.94d {+14d 56' 12"}
SUN_DIST:         79.18 [deg]   Sun_angle= -6.9 [hr] (East of Sun)
MOON_POSTN:      155.62d {+10h 22m 28s}  +12.68d {+12d 40' 39"}
MOON_DIST:        77.82 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      107.88, 35.55 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      123.70, 78.76 [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 12 Aug 18 08:35:29 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     852903,   Seg_Num: 0
GRB_RA:          245.8360d {+16h 23m 20.64s} (J2000),
                 245.7304d {+16h 22m 55.29s} (current),
                 246.1264d {+16h 24m 30.33s} (1950)
GRB_DEC:         +74.6646d {+74d 39' 52.5"} (J2000),
                 +74.6221d {+74d 37' 19.5"} (current),
                 +74.7779d {+74d 46' 40.5"} (1950)
GRB_ERROR:       2.7 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  18342 TJD;   224 DOY;   18/08/12
IMG_START_TIME:  30265.00 SOD {08:24:25.00} UT,   114.8 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       142.02d {+09h 28m 05s}  +14.94d {+14d 56' 12"}
SUN_DIST:         79.18 [deg]   Sun_angle= -6.9 [hr] (East of Sun)
MOON_POSTN:      155.62d {+10h 22m 28s}  +12.68d {+12d 40' 39"}
MOON_DIST:        77.81 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      107.89, 35.55 [deg] galactic lon,lat of the burst
ECL_COORDS:      123.72, 78.75 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        This is an Update Notice -- the RA,Dec values herein supersede the previous XRT_POS Notice.  
COMMENTS:        TAM values, flux and significance fields are not valid.  
COMMENTS:        This position was automatically generated on the ground using  
COMMENTS:        Photon Counting data telemetered via TDRSS (SPER data).  
COMMENTS:        See http://www.swift.ac.uk/sper/docs.php for details.  
COMMENTS:        This position was enhanced using UVOT field astrometry.  
COMMENTS:        The probability that this is a serendipitous source in the  
COMMENTS:        SPER window is 0.58% < P(seren) < 1.1%.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 12 Aug 18 08:36:59 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     852903,   Seg_Num: 0
POINT_RA:        245.863d {+16h 23m 27s} (J2000)
POINT_DEC:       +74.663d {+74d 39' 48"} (J2000)
ROLL:            287.241d
IMG_START_DATE:  18342 TJD;   224 DOY;   18/08/12
IMG_START_TIME:  30420.73 SOD {08:27:00.73} UT,   270.5 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     555755242
X_OFFSET:        799 [pixels]
Y_OFFSET:        936 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       959
Y_GRB_POS:       1096
BINNING_INDEX:   1
IM_URL:          sw00852903000msuni0292.fits
SUN_POSTN:       142.02d {+09h 28m 05s}  +14.94d {+14d 56' 11"}
SUN_DIST:         79.18 [deg]   Sun_angle= -6.9 [hr] (East of Sun)
MOON_POSTN:      155.63d {+10h 22m 32s}  +12.67d {+12d 40' 23"}
MOON_DIST:        77.82 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      107.88, 35.55 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      123.70, 78.76 [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 12 Aug 18 08:37:11 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     852903,   Seg_Num: 0
POINT_RA:        245.863d {+16h 23m 27s} (J2000)
POINT_DEC:       +74.663d {+74d 39' 48"} (J2000)
ROLL:            287.241d
IMG_START_DATE:  18342 TJD;   224 DOY;   18/08/12
IMG_START_TIME:  30420.73 SOD {08:27:00.73} UT,   270.5 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     555755242
X_OFFSET:        799 [pixels]
Y_OFFSET:        936 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       959
Y_GRB_POS:       1096
BINNING_INDEX:   1
IM_URL:          sw00852903000msuni0292.fits
SUN_POSTN:       142.02d {+09h 28m 05s}  +14.94d {+14d 56' 11"}
SUN_DIST:         79.18 [deg]   Sun_angle= -6.9 [hr] (East of Sun)
MOON_POSTN:      155.63d {+10h 22m 32s}  +12.67d {+12d 40' 21"}
MOON_DIST:        77.82 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      107.88, 35.55 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      123.70, 78.76 [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:        If you have elected to receive attachments:  
COMMENTS:        The uvot_catalog_image.fits.gz file does not exist; skipping the attachment.

GCN Circular #23129
A. Y. Lien (GSFC/UMBC), S. D. Barthelmy (GSFC), A. D'Ai (INAF-IASFPA), V. D'Elia (ASDC), C. Gronwall (PSU), K. L. Page (U Leicester) and E. Troja (NASA/GSFC/UMCP) report on behalf of the Neil Gehrels Swift Observatory Team:
At 08:22:30 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 180812A (trigger=852903). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 245.886, +74.670, which is
```
   RA(J2000)  =  16h 23m 33s
   Dec(J2000) = +74d 40' 11"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows several peaks with a total duration of about 25 sec. The peak count rate was ~1500 counts/sec (15-350 keV), at ~0 sec after the trigger.
The XRT began observing the field at 08:24:17.6 UT, 107.5 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source with an enhanced position: RA, Dec 245.8360, 74.6647 which is equivalent to:
```
   RA(J2000)  = 16h 23m 20.64s
   Dec(J2000) = +74d 39' 53.0"
```
with an uncertainty of 2.7 arcseconds (radius, 90% containment). This location is 51 arcseconds from the BAT onboard position, within the BAT error circle. This position may be improved as more data are received; the latest position is available at http://www.swift.ac.uk/sper. We cannot determine whether the source is fading at the present time.
A power-law fit to a spectrum formed from promptly downlinked event data gives a column density in excess of the Galactic value (4.37 x 10^20 cm^-2, Willingale et al. 2013), with an excess column of 4.8 (+4.29/-3.49) x 10^21 cm^-2 (90% confidence).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 112 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 0.04.
Burst Advocate for this burst is A. Y. Lien (amy.y.lien AT nasa.gov). 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 12 Aug 18 08:40:00 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     852903,   Seg_Num: 0
POINT_RA:        245.864d {+16h 23m 27s} (J2000)
POINT_DEC:       +74.663d {+74d 39' 48"} (J2000)
POINT_ROLL:      287.242d
IMG_START_DATE:  18342 TJD;   224 DOY;   18/08/12
IMG_START_TIME:  31023.01 SOD {08:37:03.01} UT,   872.8 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        5.086
N_STARS:         62
X_OFFSET:        240 [pixels]
Y_OFFSET:        377 [pixels]
X_MAX:           1679 [pixels]
Y_MAX:           1816 [pixels]
DET_THRESH:      19
PHOTO_THRESH:    11
SL_URL:          sw00852903000msufc0872.fits
SUN_POSTN:       142.02d {+09h 28m 06s}  +14.94d {+14d 56' 09"}
SUN_DIST:         79.18 [deg]   Sun_angle= -6.9 [hr] (East of Sun)
MOON_POSTN:      155.66d {+10h 22m 39s}  +12.66d {+12d 39' 50"}
MOON_DIST:        77.82 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      107.88, 35.55 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      123.70, 78.76 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 12 Aug 18 08:40:15 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     852903,   Seg_Num: 0
POINT_RA:        245.864d {+16h 23m 27s} (J2000)
POINT_DEC:       +74.663d {+74d 39' 48"} (J2000)
POINT_ROLL:      287.242d
IMG_START_DATE:  18342 TJD;   224 DOY;   18/08/12
IMG_START_TIME:  31023.01 SOD {08:37:03.01} UT,   872.8 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        5.086
N_STARS:         62
X_OFFSET:        240 [pixels]
Y_OFFSET:        377 [pixels]
X_MAX:           1679 [pixels]
Y_MAX:           1816 [pixels]
DET_THRESH:      19
PHOTO_THRESH:    11
SL_URL:          sw00852903000msufc0872.fits
SUN_POSTN:       142.02d {+09h 28m 06s}  +14.94d {+14d 56' 09"}
SUN_DIST:         79.18 [deg]   Sun_angle= -6.9 [hr] (East of Sun)
MOON_POSTN:      155.67d {+10h 22m 40s}  +12.66d {+12d 39' 47"}
MOON_DIST:        77.82 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      107.88, 35.55 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      123.70, 78.76 [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 12 Aug 18 08:41:27 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     852903,   Seg_Num: 0
POINT_RA:        245.864d {+16h 23m 27s} (J2000)
POINT_DEC:       +74.663d {+74d 39' 48"} (J2000)
ROLL:            287.242d
IMG_START_DATE:  18342 TJD;   224 DOY;   18/08/12
IMG_START_TIME:  31023.01 SOD {08:37:03.01} UT,   872.8 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     555755844
X_OFFSET:        799 [pixels]
Y_OFFSET:        936 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       959
Y_GRB_POS:       1096
BINNING_INDEX:   1
IM_URL:          sw00852903000msuni0894.fits
SUN_POSTN:       142.02d {+09h 28m 06s}  +14.94d {+14d 56' 08"}
SUN_DIST:         79.18 [deg]   Sun_angle= -6.9 [hr] (East of Sun)
MOON_POSTN:      155.68d {+10h 22m 43s}  +12.66d {+12d 39' 34"}
MOON_DIST:        77.82 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      107.88, 35.55 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      123.70, 78.76 [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 12 Aug 18 08:41:32 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     852903,   Seg_Num: 0
POINT_RA:        245.864d {+16h 23m 27s} (J2000)
POINT_DEC:       +74.663d {+74d 39' 48"} (J2000)
ROLL:            287.242d
IMG_START_DATE:  18342 TJD;   224 DOY;   18/08/12
IMG_START_TIME:  31023.01 SOD {08:37:03.01} UT,   872.8 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     555755844
X_OFFSET:        799 [pixels]
Y_OFFSET:        936 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       959
Y_GRB_POS:       1096
BINNING_INDEX:   1
IM_URL:          sw00852903000msuni0894.fits
SUN_POSTN:       142.02d {+09h 28m 06s}  +14.94d {+14d 56' 08"}
SUN_DIST:         79.18 [deg]   Sun_angle= -6.9 [hr] (East of Sun)
MOON_POSTN:      155.68d {+10h 22m 43s}  +12.66d {+12d 39' 34"}
MOON_DIST:        77.82 [deg]
MOON_ILLUM:      1 [%]
GAL_COORDS:      107.88, 35.55 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      123.70, 78.76 [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 #23130
I. Carrasco (Univ. de Malaga), Y. Hu, E. Fernandez-Garcia, J. C. Tello and A. J. Castro-Tirado (IAA-CSIC), D. Hiriart and W. H. Lee (UNAM), S. Jeong and I. H. Park (SKKU), M. D. Caballero-Garcia (ASU-CAS, CZ) and R. Cunniffe (Inst. of Physics, CZ) on behalf of a larger collaboration, report:
The 60cm BOOTES-5/JGT robotic telescope at Observatorio Astronomico Nacional in San Pedro Martir (Mexico) automatically responded in 22s (and 52s after the GRB onset) to the Swift trigger of GRB 180812A (Lien et al., GCNC 23129). The first image (10s exposure, r-band) was obtained at 08:23:25 UT. At the position of the Swift X-ray afterglow, a variable optical source with r about 17 mag is detected, which is fading in brightness in the late images. Therefore we propose this source to be the optical afterglow to GRB 180812A. Spectroscopic observations are encouraged.
We thank the staff at Observatorio Astronomico Nacional in San Pedro Martir for its excellent support.
GCN Circular #23131
M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team.
Using 2046 s of XRT Photon Counting mode data and 2 UVOT images for GRB 180812A, 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 = 245.83465, +74.66472 which is equivalent to:
```
RA (J2000): 16h 23m 20.32s
Dec (J2000): +74d 39' 53.0"
```
with an uncertainty of 1.7 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 #23132
Alan M. Watson (UNAM), Eleonora Troja (GSFC), Nat Butler (ASU), Rosa L. Becerra (UNAM), William H. Lee (UNAM), Carlos Rom�n-Z��iga (UNAM), and Alexander Kutyrev (GSFC) report:
We observed the field of GRB 180612A (Lien et al., GCN 23129) 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 2018-08-12 08:13.5 to 11:53:16.7 (from 11.6 seconds after the alert or 43.1 seconds after the trigger to 3.5 hours after the trigger), obtaining a total of 2.46 hours of exposure in the w filter.
We detect the optical counterpart reported by Carrasco et al. (GCN Circ. 23130). We see it rise from w = 17.4 to w = 17.2 at 160 seconds after burst, and then fade rapidly.
We note that simultaneous observations with UVOT in the white filter do not detect anything to a limit of about 19.8 (Lien et al., GCN 23129). Our w filter is much redder than the UVOT white filter, which suggests that this might be an intrinsically red afterglow or be attenuated by intergalactic absorption in the blue.
These magnitudes are calibrated against the USNO-B1 catalog (adjusted to an approximate AB system) and are 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 #23134
P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), A. D'Ai (INAF-IASFPA), S. J. LaPorte (PSU), J.A. Kennea (PSU), B. Sbarufatti (INAF-OAB/PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester) and A.Y. Lien report on behalf of the Swift-XRT team:
We have analysed 8.2 ks of XRT data for GRB 180812A (Lien et al. GCN Circ. 23129), from 114 s to 24.0 ks after the BAT trigger. The data are entirely in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Goad et al. (GCN Circ. 23131).
The light curve can be modelled with a power-law decay with a decay index of alpha=1.08 (+/-0.05).
A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 1.74 (+0.16, -0.14). The best-fitting absorption column is 6.8 (+4.3, -2.4) x 10^20 cm^-2, consistent with the Galactic value of 4.4 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 3.8 x 10^-11 (4.2 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     6.8 (+4.3, -2.4) x 10^20 cm^-2
Galactic foreground: 4.4 x 10^20 cm^-2
Excess significance: <1.6 sigma
Photon index:	     1.74 (+0.16, -0.14)
```
If the light curve continues to decay with a power-law decay index of 1.08, the count rate at T+24 hours will be 2.7 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.0 x 10^-13 (1.1 x 10^-13) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00852903.
This circular is an official product of the Swift-XRT team.
GCN Circular #23135
A. von Kienlin (MPE), R. Hamburg (UAH), and C. Meegan (UAH) report on behalf of the Fermi GBM Team:
"At 08:22:30.31 UT on 12 August 2018, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 180812A (trigger 555754955 / 180812349), which was also detected by the Swift BAT and XRT instruments (Lien et al. 2008, GCN 23129). The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight at the GBM trigger time is 46 degrees.
The GBM light curve shows several peaks with a duration (T90) of about 38 s (50-300 keV). The time-averaged spectrum from T0-2.0 s to T0+34.8 s is adequately fit by a power law function with an exponential high-energy cutoff. The power law index is -0.56 +/- 0.36 and the cutoff energy, parameterized as Epeak, is 110 +/- 25 keV.
The event fluence (10-1000 keV) in this time interval is (1.2 +/- 0.2)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0+15.7 s in the 10-1000 keV band is 2.5 +/- 0.2 ph/s/cm^2.
The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN Circular #23136
T. N. Ukwatta (LANL), S. D. Barthelmy (GSFC), J. R. Cummings (CPI), H. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU) (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 180812A (trigger #852903) (Lien et al., GCN Circ. 23129). The BAT ground-calculated position is RA, Dec = 245.839, 74.674 deg which is
```
  RA(J2000)  =  16h 23m 21.3s
  Dec(J2000) = +74d 40' 27.0"
```
with an uncertainty of 2.3 arcmin, (radius, sys+stat, 90% containment). The partial coding was 26%.
The mask-weighted light curve shows a multi-peaked structure that starts at ~T0 and ends at ~T+17 s. T90 (15-350 keV) is 16.51 +- 0.92 sec (estimated error including systematics).
The time-averaged spectrum from T-0.30 to T+16.63 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.22 +- 0.27. The fluence in the 15-150 keV band is 8.0 +- 1.4 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+15.62 sec in the 15-150 keV band is 1.9 +- 0.4 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/852903/BA/
GCN Circular #23138
GRB 180812A: Swift/UVOT Detection
S. J. LaPorte (PSU) and A. Y. Lien (GSFC/UMBC) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 180812A 112 s after the BAT trigger (Lien et al., GCN Circ. 23129). A fading source consistent with the XRT position (Goad et al. GCN Circ. 23131) is detected in the initial UVOT exposures.
The preliminary UVOT position is:
```
    RA  (J2000) =  16:23:20.45 =  245.83522 (deg.)
    Dec (J2000) = 74:39:52.9 =  74.66471 (deg.)
```
with an estimated uncertainty of 0.50 arc sec. (radius, 90% confidence), consistent with detections reported by BOOTES-5/JGT (Carrasco et al. GCN Circ. 23130) and COATLI (Watson et al. GCN Circ. 23132).
Preliminary detections and 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are:
```
Filter         T_start(s)   T_stop(s)      Exp(s)           Mag

white              140          289          431         19.81 +/- 0.17
white             1551         2092           77        >20.85
v                  600         6610          372        >18.9
b                  526         5994          352        >20.0
u                  270         5789          598        >19.8
w1                 650         6857          211        >19.5
m2                6616         6815          197        >20.2
w2                6206         6406          197        >20.2
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.04 in the direction of the burst (Schlegel et al. 1998).

Back to JG's homepage

Jochen Greiner, last update: 13-Aug-2018 [Disclaimer]