Gamma-ray Burst 111018A

(All information courtesy of the instrument teams.)

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Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 18 Oct 11 17:27:43 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     505801,   Seg_Num: 0
GRB_RA:          271.500d {+18h 06m 00s} (J2000),
                 271.656d {+18h 06m 37s} (current),
                 270.841d {+18h 03m 22s} (1950)
GRB_DEC:          -3.871d {-03d 52' 16"} (J2000),
                  -3.869d {-03d 52' 09"} (current),
                  -3.877d {-03d 52' 36"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       0 [cnts]    Image_Peak=1501 [image_cnts]
TRIGGER_DUR:     64.000 [sec] 
TRIGGER_INDEX:   20000     E_range: 15-50 keV
BKG_INTEN:       0 [cnts]
BKG_TIME:        0.00 SOD {00:00:00.00} UT
BKG_DUR:         0 [sec]
GRB_DATE:        15852 TJD;   291 DOY;   11/10/18
GRB_TIME:        62784.51 SOD {17:26:24.51} UT
GRB_PHI:         -88.69 [deg]
GRB_THETA:        16.90 [deg]
SOLN_STATUS:     0x13
RATE_SIGNIF:     0.00 [sigma]
IMAGE_SIGNIF:    7.53 [sigma]
MERIT_PARAMS:     +1  +0  +0  +6  +1  -2  +0  +1 -37  +0 
SUN_POSTN:       203.15d {+13h 32m 36s}   -9.67d {-09d 40' 15"}
SUN_DIST:         68.18 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:       98.78d {+06h 35m 08s}  +21.11d {+21d 06' 35"}
MOON_DIST:       161.42 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:       24.23,  8.29 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      271.59, 19.56 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Coordinates.  
COMMENTS:        This is an image trigger.  (The RATE_SIGNIF & BKG_{INTEN, TIME, DUR} are undefined.)  
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 = 326.14,6.92 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 18 Oct 11 17:29:03 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     505801,   Seg_Num: 0
GRB_RA:          271.4787d {+18h 05m 54.88s} (J2000),
                 271.6343d {+18h 06m 32.23s} (current),
                 270.8191d {+18h 03m 16.58s} (1950)
GRB_DEC:          -3.9140d {-03d 54' 50.4"} (J2000),
                  -3.9122d {-03d 54' 43.9"} (current),
                  -3.9196d {-03d 55' 10.4"} (1950)
GRB_ERROR:       5.9 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       7.05e-10 [erg/cm2/sec]
GRB_SIGNIF:      4.79 [sigma]
IMG_START_DATE:  15852 TJD;   291 DOY;   11/10/18
IMG_START_TIME:  62907.56 SOD {17:28:27.56} UT,   123.0 [sec] since BAT Trigger Time
TAM[0-3]:        327.65 237.22 261.51 243.36
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       203.15d {+13h 32m 36s}   -9.67d {-09d 40' 16"}
SUN_DIST:         68.15 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:       98.79d {+06h 35m 11s}  +21.11d {+21d 06' 29"}
MOON_DIST:       161.45 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:       24.18,  8.28 [deg] galactic lon,lat of the burst
ECL_COORDS:      271.57, 19.52 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 2.87 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 18 Oct 11 17:29:12 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     505801,   Seg_Num: 0
GRB_RA:          271.4787d {+18h 05m 54.8s} (J2000),
                 271.6343d {+18h 06m 32.2s} (current),
                 270.8191d {+18h 03m 16.5s} (1950)
GRB_DEC:          -3.9140d {-03d 54' 50.4"} (J2000),
                  -3.9122d {-03d 54' 43.9"} (current),
                  -3.9196d {-03d 55' 10.4"} (1950)
GRB_ERROR:       5.8 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       23 [cnts]
IMG_START_DATE:  15852 TJD;   291 DOY;   11/10/18
IMG_START_TIME:  62907.56 SOD {17:28:27.56} UT,   123.0 [sec] since BAT Trigger Time
CENTROID_X:      224.95,  raw= 225  [pixels]
CENTROID_Y:      351.56,  raw= 352  [pixels]
ROLL:            261.10 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   126.27
GRB_POS_XRT_Z:   -185.61
IMAGE_URL:       sw00505801000msxps_rw.img
SUN_POSTN:       203.15d {+13h 32m 36s}   -9.67d {-09d 40' 16"}
SUN_DIST:         68.15 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:       98.80d {+06h 35m 11s}  +21.11d {+21d 06' 29"}
MOON_DIST:       161.45 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:       24.18,  8.28 [deg] galactic lon,lat of the burst
ECL_COORDS:      271.57, 19.52 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 18 Oct 11 17:29:21 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     505801,   Seg_Num: 0
GRB_RA:          271.4787d {+18h 05m 54.8s} (J2000),
                 271.6343d {+18h 06m 32.2s} (current),
                 270.8191d {+18h 03m 16.5s} (1950)
GRB_DEC:          -3.9140d {-03d 54' 50.4"} (J2000),
                  -3.9122d {-03d 54' 43.9"} (current),
                  -3.9196d {-03d 55' 10.4"} (1950)
GRB_ERROR:       5.8 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       23 [cnts]
IMG_START_DATE:  15852 TJD;   291 DOY;   11/10/18
IMG_START_TIME:  62907.56 SOD {17:28:27.56} UT,   123.0 [sec] since BAT Trigger Time
CENTROID_X:      224.95,  raw= 225  [pixels]
CENTROID_Y:      351.56,  raw= 352  [pixels]
ROLL:            261.10 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   126.27
GRB_POS_XRT_Z:   -185.61
IMAGE_URL:       sw00505801000msxps_rw.img
SUN_POSTN:       203.15d {+13h 32m 36s}   -9.67d {-09d 40' 16"}
SUN_DIST:         68.15 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:       98.80d {+06h 35m 11s}  +21.11d {+21d 06' 28"}
MOON_DIST:       161.45 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:       24.18,  8.28 [deg] galactic lon,lat of the burst
ECL_COORDS:      271.57, 19.52 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 18 Oct 11 17:30:21 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     505801,   Seg_Num: 0
GRB_RA:          271.500d {+18h 06m 00s} (J2000),
                 271.656d {+18h 06m 37s} (current),
                 270.841d {+18h 03m 22s} (1950)
GRB_DEC:          -3.871d {-03d 52' 16"} (J2000),
                  -3.869d {-03d 52' 09"} (current),
                  -3.877d {-03d 52' 36"} (1950)
GRB_DATE:        15852 TJD;   291 DOY;   11/10/18
GRB_TIME:        62784.51 SOD {17:26:24.51} UT
TRIGGER_INDEX:   20000
GRB_PHI:         -88.69 [deg]
GRB_THETA:        16.90 [deg]
DELTA_TIME:      0.00 [sec]
TRIGGER_DUR:     64.000 [sec] 
SOLN_STATUS:     0x13
RATE_SIGNIF:     0.00 [sigma]
IMAGE_SIGNIF:    7.53 [sigma]
LC_URL:          sw00505801000msb.lc
SUN_POSTN:       203.15d {+13h 32m 36s}   -9.67d {-09d 40' 17"}
SUN_DIST:         68.18 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:       98.81d {+06h 35m 13s}  +21.11d {+21d 06' 23"}
MOON_DIST:       161.41 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:       24.23,  8.29 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      271.59, 19.56 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Lightcurve.  
COMMENTS:           
COMMENTS:        The next comments were copied from the BAT_POS Notice:  
COMMENTS:        This is an image 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 = 326.14,6.92 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 18 Oct 11 17:31:29 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     505801,   Seg_Num: 0
POINT_RA:        271.523d {+18h 06m 06s} (J2000)
POINT_DEC:        -3.872d {-03d 52' 17"} (J2000)
POINT_ROLL:      261.099d
IMG_START_DATE:  15852 TJD;   291 DOY;   11/10/18
IMG_START_TIME:  62916.63 SOD {17:28:36.63} UT,   132.1 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.511
N_STARS:         14
X_OFFSET:        656 [pixels]
Y_OFFSET:        488 [pixels]
X_MAX:           1615 [pixels]
Y_MAX:           1447 [pixels]
DET_THRESH:      16
PHOTO_THRESH:    9
SL_URL:          sw00505801000msufc0132.fits
SUN_POSTN:       203.15d {+13h 32m 36s}   -9.67d {-09d 40' 18"}
SUN_DIST:         68.20 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:       98.82d {+06h 35m 16s}  +21.11d {+21d 06' 18"}
MOON_DIST:       161.42 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:       24.24,  8.26 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      271.61, 19.56 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 18 Oct 11 17:32:00 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     505801,   Seg_Num: 0
POINT_RA:        271.523d {+18h 06m 06s} (J2000)
POINT_DEC:        -3.872d {-03d 52' 17"} (J2000)
POINT_ROLL:      261.099d
IMG_START_DATE:  15852 TJD;   291 DOY;   11/10/18
IMG_START_TIME:  62916.63 SOD {17:28:36.63} UT,   132.1 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.511
N_STARS:         14
X_OFFSET:        656 [pixels]
Y_OFFSET:        488 [pixels]
X_MAX:           1615 [pixels]
Y_MAX:           1447 [pixels]
DET_THRESH:      16
PHOTO_THRESH:    9
SL_URL:          sw00505801000msufc0132.fits
SUN_POSTN:       203.15d {+13h 32m 36s}   -9.67d {-09d 40' 19"}
SUN_DIST:         68.20 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:       98.82d {+06h 35m 17s}  +21.10d {+21d 06' 16"}
MOON_DIST:       161.42 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:       24.24,  8.26 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      271.61, 19.56 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 18 Oct 11 17:32:51 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     505801,   Seg_Num: 0
POINT_RA:        271.523d {+18h 06m 06s} (J2000)
POINT_DEC:        -3.872d {-03d 52' 17"} (J2000)
ROLL:            261.099d
IMG_START_DATE:  15852 TJD;   291 DOY;   11/10/18
IMG_START_TIME:  62916.63 SOD {17:28:36.63} UT,   132.1 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     340651724
X_OFFSET:        1015 [pixels]
Y_OFFSET:        464 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1175
Y_GRB_POS:       624
BINNING_INDEX:   1
IM_URL:          sw00505801000msuni0140.fits
SUN_POSTN:       203.15d {+13h 32m 36s}   -9.67d {-09d 40' 20"}
SUN_DIST:         68.20 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:       98.83d {+06h 35m 19s}  +21.10d {+21d 06' 12"}
MOON_DIST:       161.42 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:       24.24,  8.26 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      271.61, 19.56 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 18 Oct 11 17:33:09 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     505801,   Seg_Num: 0
POINT_RA:        271.523d {+18h 06m 06s} (J2000)
POINT_DEC:        -3.872d {-03d 52' 17"} (J2000)
ROLL:            261.099d
IMG_START_DATE:  15852 TJD;   291 DOY;   11/10/18
IMG_START_TIME:  62916.63 SOD {17:28:36.63} UT,   132.1 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     340651724
X_OFFSET:        1015 [pixels]
Y_OFFSET:        464 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1175
Y_GRB_POS:       624
BINNING_INDEX:   1
IM_URL:          sw00505801000msuni0140.fits
SUN_POSTN:       203.15d {+13h 32m 36s}   -9.67d {-09d 40' 20"}
SUN_DIST:         68.20 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:       98.83d {+06h 35m 20s}  +21.10d {+21d 06' 11"}
MOON_DIST:       161.42 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:       24.24,  8.26 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      271.61, 19.56 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 18 Oct 11 17:33:16 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     505801,   Seg_Num: 0
POINT_RA:        271.527d {+18h 06m 06s} (J2000)
POINT_DEC:        -3.871d {-03d 52' 14"} (J2000)
POINT_ROLL:      261.099d
IMG_START_DATE:  15852 TJD;   291 DOY;   11/10/18
IMG_START_TIME:  63074.81 SOD {17:31:14.81} UT,   290.3 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.033
N_STARS:         1
X_OFFSET:        695 [pixels]
Y_OFFSET:        144 [pixels]
X_MAX:           1654 [pixels]
Y_MAX:           1103 [pixels]
DET_THRESH:      3
PHOTO_THRESH:    2
SL_URL:          sw00505801000msufc0290.fits
SUN_POSTN:       203.15d {+13h 32m 36s}   -9.67d {-09d 40' 20"}
SUN_DIST:         68.20 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:       98.83d {+06h 35m 20s}  +21.10d {+21d 06' 10"}
MOON_DIST:       161.42 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:       24.24,  8.26 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      271.62, 19.56 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 18 Oct 11 17:34:28 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     505801,   Seg_Num: 0
POINT_RA:        271.527d {+18h 06m 06s} (J2000)
POINT_DEC:        -3.871d {-03d 52' 14"} (J2000)
ROLL:            261.099d
IMG_START_DATE:  15852 TJD;   291 DOY;   11/10/18
IMG_START_TIME:  63074.81 SOD {17:31:14.81} UT,   290.3 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     340651882
X_OFFSET:        1015 [pixels]
Y_OFFSET:        464 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1175
Y_GRB_POS:       624
BINNING_INDEX:   1
IM_URL:          sw00505801000msuni0298.fits
SUN_POSTN:       203.15d {+13h 32m 37s}   -9.67d {-09d 40' 21"}
SUN_DIST:         68.20 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:       98.84d {+06h 35m 23s}  +21.10d {+21d 06' 05"}
MOON_DIST:       161.41 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:       24.24,  8.26 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      271.62, 19.56 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 18 Oct 11 17:34:41 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     505801,   Seg_Num: 0
POINT_RA:        271.527d {+18h 06m 06s} (J2000)
POINT_DEC:        -3.871d {-03d 52' 14"} (J2000)
ROLL:            261.099d
IMG_START_DATE:  15852 TJD;   291 DOY;   11/10/18
IMG_START_TIME:  63074.81 SOD {17:31:14.81} UT,   290.3 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     340651882
X_OFFSET:        1015 [pixels]
Y_OFFSET:        464 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1175
Y_GRB_POS:       624
BINNING_INDEX:   1
IM_URL:          sw00505801000msuni0298.fits
SUN_POSTN:       203.15d {+13h 32m 37s}   -9.67d {-09d 40' 21"}
SUN_DIST:         68.20 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:       98.85d {+06h 35m 23s}  +21.10d {+21d 06' 04"}
MOON_DIST:       161.41 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:       24.24,  8.26 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      271.62, 19.56 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        If you have elected to receive attachments:  
COMMENTS:        The uvot_catalog_image.fits.gz file does not exist; skipping the attachment.

GCN Circular #12450
F. E. Marshall (NASA/GSFC), S. D. Barthelmy (GSFC), A. P. Beardmore (U Leicester), D. N. Burrows (PSU), M. M. Chester (PSU), V. D'Elia (ASDC), N. Gehrels (NASA/GSFC), S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU), N. P. M. Kuin (UCL-MSSL), V. Mangano (INAF-IASFPA), D. M. Palmer (LANL), M. H. Siegel (PSU), R. L. C. Starling (U Leicester), C. A. Swenson (PSU), G. Tagliaferri (INAF-OAB), E. Troja (NASA/GSFC/ORAU) and B.-B. Zhang (PSU) report on behalf of the Swift Team:
At 17:26:24 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 111018A (trigger=505801). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 271.500, -3.871 which is
```
   RA(J2000)  =  18h 06m 00s
   Dec(J2000) = -03d 52' 16"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows two weak peaks at T+0 and T+30 sec with a total duration of about 40 sec. The peak count rate was ~500 counts/sec (15-350 keV), at ~0 sec after the trigger.
The XRT began observing the field at 17:28:27.6 UT, 123.0 seconds after the BAT trigger. The position determined from promptly downlinked data differs significantly from the on-board position, suggesting that the XRT may have centroided on a cosmic ray; the initial XRT position notice should be treated with caution. Using promptly downlinked data we find an uncatalogued X-ray source located at RA, Dec 271.48887, -3.90719 which is equivalent to:
```
   RA(J2000)  = 18h 05m 57.33s
   Dec(J2000) = -03d 54' 25.9"
```
with an uncertainty of 3.8 arcseconds (radius, 90% containment). This location is 135 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 consistent with the Galactic value of 2.54 x 10^21 cm^-2 (Kalberla et al. 2005).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 132 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 2.16.
Burst Advocate for this burst is F. E. Marshall (marshall AT milkyway.gsfc.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:     Tue 18 Oct 11 17:52:48 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     505801,   Seg_Num: 0
GRB_RA:          271.4888d {+18h 05m 57.31s} (J2000),
                 271.6444d {+18h 06m 34.65s} (current),
                 270.8293d {+18h 03m 19.02s} (1950)
GRB_DEC:          -3.9071d {-03d 54' 25.5"} (J2000),
                  -3.9053d {-03d 54' 19.0"} (current),
                  -3.9127d {-03d 54' 45.8"} (1950)
GRB_ERROR:       3.8 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  15852 TJD;   291 DOY;   11/10/18
IMG_START_TIME:  62931.00 SOD {17:28:51.00} UT,   146.5 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       203.16d {+13h 32m 40s}   -9.68d {-09d 40' 38"}
SUN_DIST:         68.15 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:       99.01d {+06h 36m 03s}  +21.08d {+21d 04' 40"}
MOON_DIST:       161.39 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:       24.19,  8.28 [deg] galactic lon,lat of the burst
ECL_COORDS:      271.58, 19.52 [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:        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:     Tue 18 Oct 11 17:56:02 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     505801,   Seg_Num: 0
POINT_RA:        271.527d {+18h 06m 06s} (J2000)
POINT_DEC:        -3.871d {-03d 52' 15"} (J2000)
POINT_ROLL:      261.099d
IMG_START_DATE:  15852 TJD;   291 DOY;   11/10/18
IMG_START_TIME:  63646.18 SOD {17:40:46.18} UT,   861.7 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.778
N_STARS:         40
X_OFFSET:        455 [pixels]
Y_OFFSET:        0 [pixels]
X_MAX:           1894 [pixels]
Y_MAX:           1439 [pixels]
DET_THRESH:      16
PHOTO_THRESH:    9
SL_URL:          sw00505801000msufc0861.fits
SUN_POSTN:       203.17d {+13h 32m 40s}   -9.68d {-09d 40' 41"}
SUN_DIST:         68.19 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:       99.04d {+06h 36m 11s}  +21.07d {+21d 04' 25"}
MOON_DIST:       161.37 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:       24.24,  8.26 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      271.62, 19.56 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 18 Oct 11 17:56:20 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     505801,   Seg_Num: 0
POINT_RA:        271.527d {+18h 06m 06s} (J2000)
POINT_DEC:        -3.871d {-03d 52' 15"} (J2000)
POINT_ROLL:      261.099d
IMG_START_DATE:  15852 TJD;   291 DOY;   11/10/18
IMG_START_TIME:  63646.18 SOD {17:40:46.18} UT,   861.7 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.778
N_STARS:         40
X_OFFSET:        455 [pixels]
Y_OFFSET:        0 [pixels]
X_MAX:           1894 [pixels]
Y_MAX:           1439 [pixels]
DET_THRESH:      16
PHOTO_THRESH:    9
SL_URL:          sw00505801000msufc0861.fits
SUN_POSTN:       203.17d {+13h 32m 40s}   -9.68d {-09d 40' 41"}
SUN_DIST:         68.19 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:       99.05d {+06h 36m 11s}  +21.07d {+21d 04' 24"}
MOON_DIST:       161.37 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:       24.24,  8.26 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      271.62, 19.56 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 18 Oct 11 17:57:26 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     505801,   Seg_Num: 0
POINT_RA:        271.527d {+18h 06m 06s} (J2000)
POINT_DEC:        -3.871d {-03d 52' 15"} (J2000)
ROLL:            261.099d
IMG_START_DATE:  15852 TJD;   291 DOY;   11/10/18
IMG_START_TIME:  63646.18 SOD {17:40:46.18} UT,   861.7 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     340652453
X_OFFSET:        1014 [pixels]
Y_OFFSET:        559 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1174
Y_GRB_POS:       719
BINNING_INDEX:   1
IM_URL:          sw00505801000msuni0869.fits
SUN_POSTN:       203.17d {+13h 32m 40s}   -9.68d {-09d 40' 42"}
SUN_DIST:         68.19 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:       99.06d {+06h 36m 14s}  +21.07d {+21d 04' 19"}
MOON_DIST:       161.36 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:       24.24,  8.26 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      271.62, 19.56 [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:     Tue 18 Oct 11 17:57:39 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     505801,   Seg_Num: 0
POINT_RA:        271.527d {+18h 06m 06s} (J2000)
POINT_DEC:        -3.871d {-03d 52' 15"} (J2000)
ROLL:            261.099d
IMG_START_DATE:  15852 TJD;   291 DOY;   11/10/18
IMG_START_TIME:  63646.18 SOD {17:40:46.18} UT,   861.7 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     340652453
X_OFFSET:        1014 [pixels]
Y_OFFSET:        559 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1174
Y_GRB_POS:       719
BINNING_INDEX:   1
IM_URL:          sw00505801000msuni0869.fits
SUN_POSTN:       203.17d {+13h 32m 40s}   -9.68d {-09d 40' 42"}
SUN_DIST:         68.19 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:       99.06d {+06h 36m 14s}  +21.07d {+21d 04' 18"}
MOON_DIST:       161.36 [deg]
MOON_ILLUM:      64 [%]
GAL_COORDS:       24.24,  8.26 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      271.62, 19.56 [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 #12453
M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team.
Using 1590 s of XRT Photon Counting mode data and 2 UVOT images for GRB 111018A, 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 = 271.48854, -3.90728 which is equivalent to:
```
RA (J2000): 18h 05m 57.25s
Dec (J2000): -03d 54' 26.2"
```
with an uncertainty of 2.0 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 #12454
M. Nardini (Uni. Milano-Bicocca), J. Elliott and J. Greiner (both MPE Garching) report on behalf of the GROND team:
We observed the field of GRB111018A (Swift trigger 505801; Marhsal et al., GCN #12450) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2 m MPI/ESO telescope at La Silla Observatory (Chile).
Observations started at 23:47 UT on 18 October 2011, 6.35 hours after the trigger. They were performed at an average seeing of 2.8 and at an average airmass of 1.9.
Based on images with total exposures of 1500 s in g'r'i'z' and 1200 s in JHK, we do not detect a source within the Swift-XRT error circle reported by Goad et al. (GCN #12453) down to (all AB):
```
g' > 23.2,
r' > 23.5,
i' > 22.5,
z' > 22.2,
J  > 20.0,
H  > 18.9, 
K  > 18.6
```
Given magnitudes are calibrated against GROND zeropoints as well as 2MASS field stars and are not corrected for the expected Galactic foreground extinction corresponding to the heavy reddening of E(B-V)=2.16 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #12455
V. Mangano (INAF IASFPA) and F. E. Marshall (NASA/GSFC) reports on behalf of the Swift-XRT team:
We have analysed 11 ks of XRT data for GRB 111018A (Marshall et al. GCN Circ. 12450), from 115 s to 36.2 ks after the BAT trigger. The data comprise 37 s in Windowed Timing (WT) mode (the first 6 s were taken while Swift was slewing) with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Goad et al. (GCN. Circ 12453).
The light curve can be modelled with a power-law decay with a decay index of alpha=1.01 (+0.15, -0.13).
A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 1.8 (+0.8, -0.7). The best-fitting absorption column is 1.2 (+0.8, -0.6) x 10^22 cm^-2, in excess of the Galactic value of 2.5 x 10^21 cm^-2 (Kalberla et al. 2005). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 6.7 x 10^-11 (1.2 x 10^-10) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     1.2 (+0.8, -0.6) x 10^22 cm^-2
Galactic foreground: 2.5 x 10^21 cm^-2
Excess significance: 3.4 sigma
Photon index:	     1.8 (+0.8, -0.7)
```
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00505801.
This circular is an official product of the Swift-XRT team.
GCN Circular #12457
J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team):
Using the data set from T-239 to T+963 sec from recent telemetry downlinks, we report further analysis of BAT GRB 111018A (trigger #505801) (Marshall, et al., GCN Circ. 12450). The BAT ground-calculated position is RA, Dec = 271.482, -3.880 deg, which is
```
   RA(J2000)  =  18h 05m 55.6s 
   Dec(J2000) = -03d 52' 48.5" 
```
with an uncertainty of 2.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 80%.
The mask-weighted light curve shows a couple overlapping peaks starting at ~T-4 sec, peaking at ~T-1 and ~T+22 sec, and ending at ~T+35 sec, possibly out to T+75 sec. T90 (15-350 keV) is 36 +- 5 sec (estimated error including systematics).
The time-averaged spectrum from T-4.08 to T+37.30 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.18 +- 0.27. The fluence in the 15-150 keV band is 4.0 +- 0.7 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+21.71 sec in the 15-150 keV band is 0.4 +- 0.1 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/505801/BA/
GCN Circular #12459
A. A. Breeveld (MSSL-UCL) and F. E. Marshall (NASA/GSFC) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 111018A 132 s after the BAT trigger (Marshall et al., GCN Circ. 12450). No optical afterglow consistent with the refined XRT position (Goad et al., GCN Circ. 12453) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Poole et al. 2008, MNRAS, 383, 627) for the first finding chart (FC) exposure and subsequent exposures are:
```
Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC           132          282          147         >21.1
white              132         7508          653         >21.8
v                  462        12028          673         >20.2
b                  388         6000          333         >20.9
u                  291         5794          329         >20.6
uvw1               512         5590          314         >20.4
uvm2               487         5384          333         >20.2
uvw2               438        11672         1040         >21.4
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 2.16 in the direction of the burst (Schlegel et al. 1998).
GCN Report 345.1
GCN_Report 345.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_345_1.pdf by F.E. Marshall at NASA/GSFC titled: "Final Swift Observations of GRB 111018A"

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Jochen Greiner, last update: 19-Oct-2011 [Disclaimer]