Gamma-ray Burst 121031A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

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Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 31 Oct 12 22:50:52 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     537195,   Seg_Num: 0
GRB_RA:          170.771d {+11h 23m 05s} (J2000),
                 170.934d {+11h 23m 44s} (current),
                 170.133d {+11h 20m 32s} (1950)
GRB_DEC:          -3.511d {-03d 30' 37"} (J2000),
                  -3.581d {-03d 34' 51"} (current),
                  -3.236d {-03d 14' 09"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       5298 [cnts]    Image_Peak=475 [image_cnts]
TRIGGER_DUR:     1.024 [sec] 
TRIGGER_INDEX:   146     E_range: 25-100 keV
BKG_INTEN:       24773 [cnts]
BKG_TIME:        82214.17 SOD {22:50:14.17} UT
BKG_DUR:         8 [sec]
GRB_DATE:        16231 TJD;   305 DOY;   12/10/31
GRB_TIME:        82230.68 SOD {22:50:30.68} UT
GRB_PHI:         -31.71 [deg]
GRB_THETA:         4.61 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     35.52 [sigma]
IMAGE_SIGNIF:    15.07 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +2  +4  +0  +0 -69  +0 
SUN_POSTN:       216.53d {+14h 26m 08s}  -14.47d {-14d 28' 11"}
SUN_DIST:         46.23 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:       60.13d {+04h 00m 31s}  +19.99d {+19d 59' 10"}
MOON_DIST:       110.76 [deg]
MOON_ILLUM:      96 [%]
GAL_COORDS:      264.69, 52.67 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      172.91, -6.88 [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 = 156.46,0.19 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Wed 31 Oct 12 22:47:21 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      44
TRIGGER_NUM:     373416438
GRB_RA:          184.033d {+12h 16m 08s} (J2000),
                 184.198d {+12h 16m 48s} (current),
                 183.391d {+12h 13m 34s} (1950)
GRB_DEC:          -6.750d {-06d 45' 00"} (J2000),
                  -6.821d {-06d 49' 16"} (current),
                  -6.472d {-06d 28' 19"} (1950)
GRB_ERROR:       26.23 [deg radius, statistical plus systematic]
GRB_INTEN:       60 [cnts/sec]
DATA_SIGNIF:     5.40 [sigma]
INTEG_TIME:      4.096 [sec]
GRB_DATE:        16231 TJD;   305 DOY;   12/10/31
GRB_TIME:        82035.27 SOD {22:47:15.27} UT
GRB_PHI:         328.00 [deg]
GRB_THETA:        70.00 [deg]
DATA_TIME_SCALE: 4.0960 [sec]
HARD_RATIO:      0.66
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      96%  GRB
2nd_MOST_LIKELY:   3%  Generic Transient
DETECTORS:       0,0,0, 1,1,1, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:       216.53d {+14h 26m 07s}  -14.47d {-14d 28' 08"}
SUN_DIST:         32.64 [deg]   Sun_angle= 2.2 [hr] (West of Sun)
MOON_POSTN:       60.10d {+04h 00m 24s}  +19.98d {+19d 58' 58"}
MOON_DIST:       124.31 [deg]
MOON_ILLUM:      96 [%]
GAL_COORDS:      287.50, 55.06 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      186.38, -4.59 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 239.08,-19.05 [deg].

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Wed 31 Oct 12 22:47:27 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      57
TRIGGER_NUM:     373416438
GRB_RA:          176.367d {+11h 45m 28s} (J2000),
                 176.532d {+11h 46m 08s} (current),
                 175.724d {+11h 42m 54s} (1950)
GRB_DEC:          +6.267d {+06d 16' 00"} (J2000),
                  +6.195d {+06d 11' 43"} (current),
                  +6.544d {+06d 32' 40"} (1950)
GRB_ERROR:       11.67 [deg radius, statistical plus systematic]
GRB_INTEN:       180 [cnts/sec]
DATA_SIGNIF:     11.60 [sigma]
INTEG_TIME:      2.048 [sec]
GRB_DATE:        16231 TJD;   305 DOY;   12/10/31
GRB_TIME:        82035.27 SOD {22:47:15.27} UT
GRB_PHI:         312.00 [deg]
GRB_THETA:        70.00 [deg]
DATA_TIME_SCALE: 2.0480 [sec]
HARD_RATIO:      0.51
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      95%  GRB
2nd_MOST_LIKELY:   4%  Generic Transient
DETECTORS:       0,0,0, 1,1,1, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:       216.53d {+14h 26m 07s}  -14.47d {-14d 28' 09"}
SUN_DIST:         44.73 [deg]   Sun_angle= 2.7 [hr] (West of Sun)
MOON_POSTN:       60.10d {+04h 00m 24s}  +19.98d {+19d 58' 59"}
MOON_DIST:       112.27 [deg]
MOON_ILLUM:      96 [%]
GAL_COORDS:      263.03, 63.90 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      174.17,  4.31 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 239.08,-19.05 [deg].

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Wed 31 Oct 12 22:47:30 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      56
TRIGGER_NUM:     373416438
GRB_RA:          174.940d {+11h 39m 46s} (J2000),
                 175.104d {+11h 40m 25s} (current),
                 174.301d {+11h 37m 12s} (1950)
GRB_DEC:          -3.380d {-03d 22' 47"} (J2000),
                  -3.451d {-03d 27' 03"} (current),
                  -3.103d {-03d 06' 09"} (1950)
GRB_ERROR:       8.48 [deg radius, statistical only]
DATA_SIGNIF:     8.80 [sigma]
DATA_INTERVAL:   4.096 [sec]
GRB_DATE:        16231 TJD;   305 DOY;   12/10/31
GRB_TIME:        82035.27 SOD {22:47:15.27} UT
GRB_PHI:         320.00 [deg]
GRB_THETA:        76.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4143 (Gnd S/W Version number)
SUN_POSTN:       216.53d {+14h 26m 07s}  -14.47d {-14d 28' 09"}
SUN_DIST:         42.29 [deg]   Sun_angle= 2.8 [hr] (West of Sun)
MOON_POSTN:       60.10d {+04h 00m 24s}  +19.98d {+19d 58' 59"}
MOON_DIST:       114.65 [deg]
MOON_ILLUM:      96 [%]
GAL_COORDS:      270.62, 54.93 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      176.70, -5.11 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Wed 31 Oct 12 22:47:34 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      67
TRIGGER_NUM:     373416438
GRB_RA:          162.870d {+10h 51m 29s} (J2000),
                 163.031d {+10h 52m 07s} (current),
                 162.244d {+10h 48m 59s} (1950)
GRB_DEC:         -10.300d {-10d 18' 00"} (J2000),
                 -10.368d {-10d 22' 05"} (current),
                 -10.034d {-10d 02' 03"} (1950)
GRB_ERROR:       5.54 [deg radius, statistical only]
DATA_SIGNIF:     19.00 [sigma]
DATA_INTERVAL:   4.096 [sec]
GRB_DATE:        16231 TJD;   305 DOY;   12/10/31
GRB_TIME:        82035.27 SOD {22:47:15.27} UT
GRB_PHI:         320.00 [deg]
GRB_THETA:        90.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4143 (Gnd S/W Version number)
SUN_POSTN:       216.53d {+14h 26m 07s}  -14.47d {-14d 28' 09"}
SUN_DIST:         52.30 [deg]   Sun_angle= 3.6 [hr] (West of Sun)
MOON_POSTN:       60.10d {+04h 00m 24s}  +19.98d {+19d 58' 59"}
MOON_DIST:       105.57 [deg]
MOON_ILLUM:      96 [%]
GAL_COORDS:      261.01, 42.60 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      168.30,-16.22 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 31 Oct 12 22:52:22 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     537195,   Seg_Num: 0
GRB_RA:          170.7694d {+11h 23m 04.65s} (J2000),
                 170.9331d {+11h 23m 43.95s} (current),
                 170.1316d {+11h 20m 31.58s} (1950)
GRB_DEC:          -3.5153d {-03d 30' 55.0"} (J2000),
                  -3.5858d {-03d 35' 09.0"} (current),
                  -3.2408d {-03d 14' 26.7"} (1950)
GRB_ERROR:       4.8 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       5.90e-09 [erg/cm2/sec]
GRB_SIGNIF:      12.28 [sigma]
IMG_START_DATE:  16231 TJD;   305 DOY;   12/10/31
IMG_START_TIME:  82292.63 SOD {22:51:32.63} UT,   62.0 [sec] since BAT Trigger Time
TAM[0-3]:        327.65 237.21 261.41 243.76
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       216.53d {+14h 26m 08s}  -14.47d {-14d 28' 12"}
SUN_DIST:         46.23 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:       60.14d {+04h 00m 34s}  +19.99d {+19d 59' 15"}
MOON_DIST:       110.75 [deg]
MOON_ILLUM:      96 [%]
GAL_COORDS:      264.69, 52.67 [deg] galactic lon,lat of the burst
ECL_COORDS:      172.91, -6.89 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 0.29 arcmin from the BAT position.  
COMMENTS:        The object found at this position is either a very bright burst or a cosmic ray hit.  
COMMENTS:        Examine the XRT Image to differentiate (CRs are much more compact); see examples at:  
COMMENTS:        http://www.swift.psu.edu/xrt/XRT_Postage_Stamp_Image_Photo_Gallery.htm .

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 31 Oct 12 22:52:32 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     537195,   Seg_Num: 0
GRB_RA:          170.7694d {+11h 23m 04.6s} (J2000),
                 170.9331d {+11h 23m 43.9s} (current),
                 170.1316d {+11h 20m 31.5s} (1950)
GRB_DEC:          -3.5153d {-03d 30' 55.0"} (J2000),
                  -3.5858d {-03d 35' 09.0"} (current),
                  -3.2408d {-03d 14' 26.7"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       151 [cnts]
IMG_START_DATE:  16231 TJD;   305 DOY;   12/10/31
IMG_START_TIME:  82292.63 SOD {22:51:32.63} UT,   62.0 [sec] since BAT Trigger Time
CENTROID_X:      317.82,  raw= 318  [pixels]
CENTROID_Y:      308.61,  raw= 309  [pixels]
ROLL:            106.73 [deg]
GAIN:            2
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   25.01
GRB_POS_XRT_Z:   33.28
IMAGE_URL:       sw00537195000msxps_rw.img
SUN_POSTN:       216.53d {+14h 26m 08s}  -14.47d {-14d 28' 13"}
SUN_DIST:         46.23 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:       60.14d {+04h 00m 35s}  +19.99d {+19d 59' 15"}
MOON_DIST:       110.75 [deg]
MOON_ILLUM:      96 [%]
GAL_COORDS:      264.69, 52.67 [deg] galactic lon,lat of the burst
ECL_COORDS:      172.91, -6.89 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.  
COMMENTS:        The object found at this position is either a very bright burst or a cosmic ray hit.  
COMMENTS:        Examine the XRT Image to differentiate (CRs are much more compact); see examples at:  
COMMENTS:        http://www.swift.psu.edu/xrt/XRT_Postage_Stamp_Image_Photo_Gallery.htm .

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 31 Oct 12 22:52:44 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     537195,   Seg_Num: 0
GRB_RA:          170.7694d {+11h 23m 04.6s} (J2000),
                 170.9331d {+11h 23m 43.9s} (current),
                 170.1316d {+11h 20m 31.5s} (1950)
GRB_DEC:          -3.5153d {-03d 30' 55.0"} (J2000),
                  -3.5858d {-03d 35' 09.0"} (current),
                  -3.2408d {-03d 14' 26.7"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       151 [cnts]
IMG_START_DATE:  16231 TJD;   305 DOY;   12/10/31
IMG_START_TIME:  82292.63 SOD {22:51:32.63} UT,   62.0 [sec] since BAT Trigger Time
CENTROID_X:      317.82,  raw= 318  [pixels]
CENTROID_Y:      308.61,  raw= 309  [pixels]
ROLL:            106.73 [deg]
GAIN:            2
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   25.01
GRB_POS_XRT_Z:   33.28
IMAGE_URL:       sw00537195000msxps_rw.img
SUN_POSTN:       216.53d {+14h 26m 08s}  -14.47d {-14d 28' 13"}
SUN_DIST:         46.23 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:       60.15d {+04h 00m 35s}  +19.99d {+19d 59' 16"}
MOON_DIST:       110.75 [deg]
MOON_ILLUM:      96 [%]
GAL_COORDS:      264.69, 52.67 [deg] galactic lon,lat of the burst
ECL_COORDS:      172.91, -6.89 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.  
COMMENTS:        The object found at this position is either a very bright burst or a cosmic ray hit.  
COMMENTS:        Examine the XRT Image to differentiate (CRs are much more compact); see examples at:  
COMMENTS:        http://www.swift.psu.edu/xrt/XRT_Postage_Stamp_Image_Photo_Gallery.htm .

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 31 Oct 12 22:54:27 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     537195,   Seg_Num: 0
GRB_RA:          170.771d {+11h 23m 05s} (J2000),
                 170.934d {+11h 23m 44s} (current),
                 170.133d {+11h 20m 32s} (1950)
GRB_DEC:          -3.511d {-03d 30' 37"} (J2000),
                  -3.581d {-03d 34' 51"} (current),
                  -3.236d {-03d 14' 09"} (1950)
GRB_DATE:        16231 TJD;   305 DOY;   12/10/31
GRB_TIME:        82230.68 SOD {22:50:30.68} UT
TRIGGER_INDEX:   146
GRB_PHI:         -31.71 [deg]
GRB_THETA:         4.61 [deg]
DELTA_TIME:      -50.00 [sec]
TRIGGER_DUR:     1.024 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     35.52 [sigma]
IMAGE_SIGNIF:    15.07 [sigma]
LC_URL:          sw00537195000msb.lc
SUN_POSTN:       216.53d {+14h 26m 08s}  -14.47d {-14d 28' 14"}
SUN_DIST:         46.23 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:       60.16d {+04h 00m 39s}  +19.99d {+19d 59' 21"}
MOON_DIST:       110.73 [deg]
MOON_ILLUM:      96 [%]
GAL_COORDS:      264.69, 52.67 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      172.91, -6.88 [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 = 156.46,0.19 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 31 Oct 12 23:00:28 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     537195,   Seg_Num: 0
POINT_RA:        170.776d {+11h 23m 06s} (J2000)
POINT_DEC:        -3.525d {-03d 31' 29"} (J2000)
POINT_ROLL:      106.727d
IMG_START_DATE:  16231 TJD;   305 DOY;   12/10/31
IMG_START_TIME:  82300.88 SOD {22:51:40.88} UT,   70.2 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        8.221
N_STARS:         6
X_OFFSET:        384 [pixels]
Y_OFFSET:        520 [pixels]
X_MAX:           1343 [pixels]
Y_MAX:           1479 [pixels]
DET_THRESH:      25
PHOTO_THRESH:    16
SL_URL:          sw00537195000msufc0070.fits
SUN_POSTN:       216.54d {+14h 26m 09s}  -14.47d {-14d 28' 19"}
SUN_DIST:         46.23 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:       60.21d {+04h 00m 51s}  +19.99d {+19d 59' 41"}
MOON_DIST:       110.69 [deg]
MOON_ILLUM:      96 [%]
GAL_COORDS:      264.71, 52.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      172.92, -6.89 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 31 Oct 12 23:00:50 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     537195,   Seg_Num: 0
POINT_RA:        170.776d {+11h 23m 06s} (J2000)
POINT_DEC:        -3.525d {-03d 31' 29"} (J2000)
POINT_ROLL:      106.727d
IMG_START_DATE:  16231 TJD;   305 DOY;   12/10/31
IMG_START_TIME:  82300.88 SOD {22:51:40.88} UT,   70.2 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        8.221
N_STARS:         6
X_OFFSET:        384 [pixels]
Y_OFFSET:        520 [pixels]
X_MAX:           1343 [pixels]
Y_MAX:           1479 [pixels]
DET_THRESH:      25
PHOTO_THRESH:    16
SL_URL:          sw00537195000msufc0070.fits
SUN_POSTN:       216.54d {+14h 26m 09s}  -14.47d {-14d 28' 19"}
SUN_DIST:         46.23 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:       60.22d {+04h 00m 52s}  +19.99d {+19d 59' 42"}
MOON_DIST:       110.69 [deg]
MOON_ILLUM:      96 [%]
GAL_COORDS:      264.71, 52.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      172.92, -6.89 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        If you have elected to receive attachments:  
COMMENTS:        The uvot_catalog_srclist.fits.gz file does not exist; skipping the attachment.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 31 Oct 12 23:03:49 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     537195,   Seg_Num: 0
POINT_RA:        170.776d {+11h 23m 06s} (J2000)
POINT_DEC:        -3.525d {-03d 31' 29"} (J2000)
ROLL:            106.727d
IMG_START_DATE:  16231 TJD;   305 DOY;   12/10/31
IMG_START_TIME:  82300.88 SOD {22:51:40.88} UT,   70.2 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     373416710
X_OFFSET:        719 [pixels]
Y_OFFSET:        866 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       879
Y_GRB_POS:       1026
BINNING_INDEX:   1
IM_URL:          sw00537195000msuni0080.fits
SUN_POSTN:       216.54d {+14h 26m 10s}  -14.47d {-14d 28' 22"}
SUN_DIST:         46.23 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:       60.24d {+04h 00m 58s}  +20.00d {+19d 59' 51"}
MOON_DIST:       110.67 [deg]
MOON_ILLUM:      96 [%]
GAL_COORDS:      264.71, 52.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      172.92, -6.89 [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:     Wed 31 Oct 12 23:04:13 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     537195,   Seg_Num: 0
POINT_RA:        170.776d {+11h 23m 06s} (J2000)
POINT_DEC:        -3.525d {-03d 31' 29"} (J2000)
ROLL:            106.727d
IMG_START_DATE:  16231 TJD;   305 DOY;   12/10/31
IMG_START_TIME:  82300.88 SOD {22:51:40.88} UT,   70.2 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     373416710
X_OFFSET:        719 [pixels]
Y_OFFSET:        866 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       879
Y_GRB_POS:       1026
BINNING_INDEX:   1
IM_URL:          sw00537195000msuni0080.fits
SUN_POSTN:       216.54d {+14h 26m 10s}  -14.47d {-14d 28' 22"}
SUN_DIST:         46.23 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:       60.25d {+04h 00m 59s}  +20.00d {+19d 59' 53"}
MOON_DIST:       110.66 [deg]
MOON_ILLUM:      96 [%]
GAL_COORDS:      264.71, 52.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      172.92, -6.89 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        If you have elected to receive attachments:  
COMMENTS:        The uvot_catalog_image.fits.gz file does not exist; skipping the attachment.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 31 Oct 12 23:08:22 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     537195,   Seg_Num: 0
POINT_RA:        170.776d {+11h 23m 06s} (J2000)
POINT_DEC:        -3.524d {-03d 31' 25"} (J2000)
POINT_ROLL:      106.729d
IMG_START_DATE:  16231 TJD;   305 DOY;   12/10/31
IMG_START_TIME:  82512.97 SOD {22:55:12.97} UT,   282.3 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        2.790
N_STARS:         3
X_OFFSET:        399 [pixels]
Y_OFFSET:        546 [pixels]
X_MAX:           1358 [pixels]
Y_MAX:           1505 [pixels]
DET_THRESH:      14
PHOTO_THRESH:    7
SL_URL:          sw00537195000msufc0282.fits
SUN_POSTN:       216.54d {+14h 26m 10s}  -14.47d {-14d 28' 25"}
SUN_DIST:         46.23 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:       60.28d {+04h 01m 08s}  +20.00d {+20d 00' 06"}
MOON_DIST:       110.63 [deg]
MOON_ILLUM:      96 [%]
GAL_COORDS:      264.71, 52.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      172.92, -6.89 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 31 Oct 12 23:09:57 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     537195,   Seg_Num: 0
POINT_RA:        170.776d {+11h 23m 06s} (J2000)
POINT_DEC:        -3.524d {-03d 31' 25"} (J2000)
ROLL:            106.729d
IMG_START_DATE:  16231 TJD;   305 DOY;   12/10/31
IMG_START_TIME:  82512.97 SOD {22:55:12.97} UT,   282.3 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     373416922
X_OFFSET:        719 [pixels]
Y_OFFSET:        866 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       879
Y_GRB_POS:       1026
BINNING_INDEX:   1
IM_URL:          sw00537195000msuni0292.fits
SUN_POSTN:       216.54d {+14h 26m 11s}  -14.47d {-14d 28' 26"}
SUN_DIST:         46.23 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:       60.30d {+04h 01m 11s}  +20.00d {+20d 00' 11"}
MOON_DIST:       110.61 [deg]
MOON_ILLUM:      96 [%]
GAL_COORDS:      264.71, 52.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      172.92, -6.89 [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:     Wed 31 Oct 12 23:10:24 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     537195,   Seg_Num: 0
POINT_RA:        170.776d {+11h 23m 06s} (J2000)
POINT_DEC:        -3.524d {-03d 31' 25"} (J2000)
ROLL:            106.729d
IMG_START_DATE:  16231 TJD;   305 DOY;   12/10/31
IMG_START_TIME:  82512.97 SOD {22:55:12.97} UT,   282.3 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     373416922
X_OFFSET:        719 [pixels]
Y_OFFSET:        866 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       879
Y_GRB_POS:       1026
BINNING_INDEX:   1
IM_URL:          sw00537195000msuni0292.fits
SUN_POSTN:       216.54d {+14h 26m 11s}  -14.47d {-14d 28' 27"}
SUN_DIST:         46.23 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:       60.30d {+04h 01m 12s}  +20.00d {+20d 00' 12"}
MOON_DIST:       110.61 [deg]
MOON_ILLUM:      96 [%]
GAL_COORDS:      264.71, 52.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      172.92, -6.89 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        If you have elected to receive attachments:  
COMMENTS:        The uvot_catalog_image.fits.gz file does not exist; skipping the attachment.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 31 Oct 12 23:14:45 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     537195,   Seg_Num: 0
POINT_RA:        170.776d {+11h 23m 06s} (J2000)
POINT_DEC:        -3.524d {-03d 31' 25"} (J2000)
POINT_ROLL:      106.728d
IMG_START_DATE:  16231 TJD;   305 DOY;   12/10/31
IMG_START_TIME:  83089.66 SOD {23:04:49.66} UT,   859.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        0.452
N_STARS:         190
X_OFFSET:        159 [pixels]
Y_OFFSET:        306 [pixels]
X_MAX:           1598 [pixels]
Y_MAX:           1745 [pixels]
DET_THRESH:      6
PHOTO_THRESH:    3
SL_URL:          sw00537195000msufc0858.fits
SUN_POSTN:       216.55d {+14h 26m 11s}  -14.48d {-14d 28' 30"}
SUN_DIST:         46.24 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:       60.34d {+04h 01m 21s}  +20.01d {+20d 00' 26"}
MOON_DIST:       110.58 [deg]
MOON_ILLUM:      96 [%]
GAL_COORDS:      264.71, 52.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      172.92, -6.89 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 31 Oct 12 23:15:06 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     537195,   Seg_Num: 0
POINT_RA:        170.776d {+11h 23m 06s} (J2000)
POINT_DEC:        -3.524d {-03d 31' 25"} (J2000)
POINT_ROLL:      106.728d
IMG_START_DATE:  16231 TJD;   305 DOY;   12/10/31
IMG_START_TIME:  83089.66 SOD {23:04:49.66} UT,   859.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        0.452
N_STARS:         190
X_OFFSET:        159 [pixels]
Y_OFFSET:        306 [pixels]
X_MAX:           1598 [pixels]
Y_MAX:           1745 [pixels]
DET_THRESH:      6
PHOTO_THRESH:    3
SL_URL:          sw00537195000msufc0858.fits
SUN_POSTN:       216.55d {+14h 26m 12s}  -14.48d {-14d 28' 31"}
SUN_DIST:         46.24 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:       60.34d {+04h 01m 22s}  +20.01d {+20d 00' 27"}
MOON_DIST:       110.57 [deg]
MOON_ILLUM:      96 [%]
GAL_COORDS:      264.71, 52.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      172.92, -6.89 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        If you have elected to receive attachments:  
COMMENTS:        The uvot_catalog_srclist.fits.gz file does not exist; skipping the attachment.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 31 Oct 12 23:16:37 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     537195,   Seg_Num: 0
POINT_RA:        170.776d {+11h 23m 06s} (J2000)
POINT_DEC:        -3.524d {-03d 31' 25"} (J2000)
ROLL:            106.728d
IMG_START_DATE:  16231 TJD;   305 DOY;   12/10/31
IMG_START_TIME:  83089.66 SOD {23:04:49.66} UT,   859.0 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     373417499
X_OFFSET:        718 [pixels]
Y_OFFSET:        865 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       878
Y_GRB_POS:       1025
BINNING_INDEX:   1
IM_URL:          sw00537195000msuni0868.fits
SUN_POSTN:       216.55d {+14h 26m 12s}  -14.48d {-14d 28' 32"}
SUN_DIST:         46.24 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:       60.35d {+04h 01m 25s}  +20.01d {+20d 00' 32"}
MOON_DIST:       110.56 [deg]
MOON_ILLUM:      96 [%]
GAL_COORDS:      264.71, 52.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      172.92, -6.89 [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 31 Oct 12 23:16:58 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     537195,   Seg_Num: 0
POINT_RA:        170.776d {+11h 23m 06s} (J2000)
POINT_DEC:        -3.524d {-03d 31' 25"} (J2000)
ROLL:            106.728d
IMG_START_DATE:  16231 TJD;   305 DOY;   12/10/31
IMG_START_TIME:  83089.66 SOD {23:04:49.66} UT,   859.0 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     373417499
X_OFFSET:        718 [pixels]
Y_OFFSET:        865 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       878
Y_GRB_POS:       1025
BINNING_INDEX:   1
IM_URL:          sw00537195000msuni0868.fits
SUN_POSTN:       216.55d {+14h 26m 12s}  -14.48d {-14d 28' 32"}
SUN_DIST:         46.24 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:       60.36d {+04h 01m 26s}  +20.01d {+20d 00' 33"}
MOON_DIST:       110.56 [deg]
MOON_ILLUM:      96 [%]
GAL_COORDS:      264.71, 52.67 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      172.92, -6.89 [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 NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 31 Oct 12 23:17:37 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     537195,   Seg_Num: 0
GRB_RA:          170.7704d {+11h 23m 04.89s} (J2000),
                 170.9341d {+11h 23m 44.19s} (current),
                 170.1326d {+11h 20m 31.82s} (1950)
GRB_DEC:          -3.5171d {-03d 31' 01.5"} (J2000),
                  -3.5876d {-03d 35' 15.5"} (current),
                  -3.2426d {-03d 14' 33.1"} (1950)
GRB_ERROR:       2.0 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  16231 TJD;   305 DOY;   12/10/31
IMG_START_TIME:  82574.00 SOD {22:56:14.00} UT,   343.3 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       216.55d {+14h 26m 12s}  -14.48d {-14d 28' 33"}
SUN_DIST:         46.25 [deg]   Sun_angle= 3.0 [hr] (West of Sun)
MOON_POSTN:       60.36d {+04h 01m 27s}  +20.01d {+20d 00' 35"}
MOON_DIST:       110.54 [deg]
MOON_ILLUM:      96 [%]
GAL_COORDS:      264.69, 52.67 [deg] galactic lon,lat of the burst
ECL_COORDS:      172.91, -6.89 [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 #13934
V. D'Elia (ASDC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU), M. M. Chester (PSU), J. R. Cummings (NASA/UMBC), N. Gehrels (NASA/GSFC), S. T. Holland (STScI), J. A. Kennea (PSU), F. E. Marshall (NASA/GSFC) and D. M. Palmer (LANL) report on behalf of the Swift Team:
At 22:50:30 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 121031A (trigger=537195). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 170.771, -3.511 which is
```
   RA(J2000)  =  11h 23m 05s
   Dec(J2000) = -03d 30' 37"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows a large peak with several smaller peaks riding on top with a total duration of about 50 sec. The peak count rate was ~4000 counts/sec (15-350 keV), at ~4 sec after the trigger.
The XRT began observing the field at 22:51:32.6 UT, 61.9 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 170.7694, -3.5153 which is equivalent to:
```
   RA(J2000)  = +11h 23m 4.66s
   Dec(J2000) = -03d 30' 55.1"
```
with an uncertainty of 4.8 arcseconds (radius, 90% containment). This location is 17 arcseconds from the BAT onboard position, within the BAT error circle. Despite the onboard localisation, no X-ray source was detected in 732 s of promptly-downlinked data, suggesting that the initial centroid may equally have been a cosmic ray. This position should therefore be treated with caution.
The initial flux in the 2.5 s image was 5.90e-09 erg cm^-2 s^-1 (0.2-10 keV).
UVOT took a finding chart exposure of 150 seconds with the White filter starting 70 seconds after the BAT trigger. No aspect solution is available for the 2.7'x2.7' sub-image; results from the list of sources generated on-board are not available at this time. The expected extinction corresponding to E(B-V) of 0.05.
We note that the XRT position is 1.4 arcminutes from the galaxy 2MASX J11225935-0331287, at redshift 0.1126, which has a nominal radius of 0.3 arcminutes according to NED.
Burst Advocate for this burst is V. D'Elia (delia AT asdc.asi.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 Circular #13935
P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team:
Using promptly downlinked XRT event data for GRB 121031A, we find an enhanced XRT position of the afterglow: RA, Dec: 170.7705, -3.5172 which is equivalent to:
```
   RA (J2000)  = 11 23 04.91
   Dec (J2000) = -03 31 01.9
```
with an uncertainty of 2.0 arcseconds (radius, 90% confidence). Analysis of the promptly available data is online at http://www.swift.ac.uk/sper/537195.
Position enhancement is is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177).
This circular is an official product of the Swift-XRT team.
GCN Circular #13936
GRB 121031A: Swift-BAT refined analysis
S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), V. D'Elia (ASDC), E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), 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-61 to T+243 sec from recent telemetry downlinks, we report further analysis of BAT GRB 121031A (trigger #537195) (D'Elia, et al., GCN Circ. 13934). The BAT ground-calculated position is RA, Dec = 170.772, -3.513 deg, which is
```
   RA(J2000)  =  11h 23m 05.2s 
   Dec(J2000) = -03d 30' 47.7" 
```
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 100%.
The mask-weighted light curve shows a FRED-like peak with a couple smaller peaks superposed. It starts at ~T-10 sec, peaks at ~T+4 sec, and ends at ~T+100 sec. T90 (15-350 keV) is 62.5 +- 25.1 sec (estimated error including systematics).
The time-averaged spectrum from T-2.64 to T+98.31 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.59 +- 0.07. The fluence in the 15-150 keV band is 3.1 +- 0.1 x 10^-06 erg/cm2. The 1-sec peak photon flux measured from T+4.10 sec in the 15-150 keV band is 2.2 +- 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/537195/BA/
GCN Circular #13944
M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team.
Using 4059 s of XRT Photon Counting mode data and 5 UVOT images for GRB 121031A, 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 = 170.77019, -3.51704 which is equivalent to:
```
RA (J2000): 11h 23m 4.85s
Dec (J2000): -03d 31' 01.3"
```
with an uncertainty of 1.4 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 #13946
V. D'Elia (ASDC) reports on behalf of the Swift-XRT team:
We have analysed 9.2 ks of XRT data for GRB 121031A (D'Elia et al. GCN Circ. 13934), from 68 s to 22.6 ks after the BAT trigger. The data comprise 276 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Goad et al. (GCN. Circ 13935, 13944).
The late-time light curve (from T0+4.7 ks) can be modelled with a power-law decay with a decay index of alpha=0.86 (+/-0.07).
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 2.03 (+/-0.08). The best-fitting absorption column is 4.6 (+0.4, -0.3) x 10^21 cm^-2, in excess of the Galactic value of 4.0 x 10^20 cm^-2 (Kalberla et al. 2005). The PC mode spectrum has a photon index of 2.33 (+/-0.10) and a best-fitting absorption column of 5.2 (+/-0.4) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.9 x 10^-11 (9.1 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     5.2 (+/-0.4) x 10^21 cm^-2
Galactic foreground: 4.0 x 10^20 cm^-2
Excess significance: 18.5 sigma
Photon index:	     2.33 (+/-0.10)
```
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00537195.
This circular is an official product of the Swift-XRT team.
GCN Circular #13947
S. R. Oates (MSSL-UCL) and V. D'Elia (ASDC) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 121031A 70 s after the BAT trigger (D'Elia et al., GCN Circ. 13934). No optical afterglow consistent with the enhanced XRT position (Goad et al., GCN Circ. 13944) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent exposures are:
```
Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC            70          220          147         >19.9
white             5366         7002          393         >20.5
v                 5776        11730          787         >19.4
b                 5161        18152          492         >20.0
u                16939        17239          295         >19.5
w1                4751        16932         1279         >20.5
m2                4545        22572         1870         >21.1
w2                5572        11120         1082         >20.8
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.05 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #13949
GRB 121031A, Early peak observed with Swift-BAT
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/UMD), D. M. Palmer (LANL), A. M. Parsons (GSFC), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. N. Ukwatta (GWU) (i.e. the Swift-BAT team):
With an additional data set from T-240 to T-61 sec, we report further analysis of BAT GRB 121031 (trigger #537195) (D'Elia, et al., GCN Circ. 13934). In an earlier circular (Barthelmy, et al., GCN Circ. 13936) we described the second of two equal-sized peaks from this burst. BAT triggered on that second peak. The earlier peak occurred during a pre- planned slew maneuver, and its time interval was not covered by the data available at the time the circular was produced.
The entire burst had two large peaks at T-190 and T0 that were about the same in flux, duration, and shape. Each was a FRED about 60 seconds long as seen in BAT. There was a small peak at T-50 sec of about 5 seconds duration. For the entire burst, T90 (15-350 keV) was 226 +- 19 sec (estimated error including systematics).
The time-averaged spectrum from T-209.0 to T+98.3 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.50 +- 0.05. The fluence in the 15-150 keV band is 7.8 +- 0.2 x 10^-06 erg/cm2. The 1-sec peak photon flux measured from T-190.72 sec in the 15-150 keV band is 2.4 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
GCN Circular #13951
A. Goldstein (UAH) and C.A. Meegan (USRA) report on behalf of the Fermi GBM Team:
"At 22:47:15.27 UT on 31 October 2012, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 121031A (trigger 373416438 / 121031949). which was also detected by the Swift/BAT (V. D'Elia et al. 2012, GCN 13934). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight is 85 degrees. This burst was also independently detected by INTEGRAL SPI-ACS.
The GBM light curve consists of two main pulses separated by a long quiescent period with a total burst duration (T90) of about 242 s (50-300 keV) with a possible soft tail out to about T0+500 s. The time-averaged spectrum from T0=-47 s to T0+297 s is adequately fit by a power law function with an exponential high-energy cutoff. The power law index is -0.87 +/- 0.07 and the cutoff energy, parameterized a as Epeak, is 142.3 +/- 10.8 keV
The event fluence (10-1000 keV) in this time interval is (1.99 +/- 0.09)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+4.6 s in the 8-1000 keV band is 7.4 +/- 0.7 ph/s/cm^2.
The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN Report 400.1
GCN_Report 400.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_400_1.pdf by V. DElia at ASDC titled: "Swift Observations of GRB 121031A"

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Jochen Greiner, last update: 07-Nov-2012 [Disclaimer]